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Default setting for enable_hashagg_disk
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* Default setting for enable_hashagg_disk
@ 2020-04-07 18:20  Jeff Davis <pgsql@j-davis.com>
  0 siblings, 1 reply; 275+ messages in thread

From: Jeff Davis @ 2020-04-07 18:20 UTC (permalink / raw)
  To: pgsql-hackers

This is just a placeholder thread for an open item that I'm adding to
the Open Items list. We can make a decision later.

Now that we have Disk-based Hash Aggregation, there are a lot more
situations where the planner can choose HashAgg. The
enable_hashagg_disk GUC, if set to true, chooses HashAgg based on
costing. If false, it only generates a HashAgg path if it thinks it
will fit in work_mem, similar to the old behavior (though it wlil now
spill to disk if the planner was wrong about it fitting in work_mem).
The current default is true.

I expect this to be a win in a lot of cases, obviously. But as with any
planner change, it will be wrong sometimes. We may want to be
conservative and set the default to false depending on the experience
during beta. I'm inclined to leave it as true for now though, because
that will give us better information upon which to base any decision.

Regards,
	Jeff Davis







^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* Re: Default setting for enable_hashagg_disk
@ 2020-04-07 22:39  Justin Pryzby <pryzby@telsasoft.com>
  parent: Jeff Davis <pgsql@j-davis.com>
  0 siblings, 1 reply; 275+ messages in thread

From: Justin Pryzby @ 2020-04-07 22:39 UTC (permalink / raw)
  To: Jeff Davis <pgsql@j-davis.com>; +Cc: pgsql-hackers

On Tue, Apr 07, 2020 at 11:20:46AM -0700, Jeff Davis wrote:
> The enable_hashagg_disk GUC, if set to true, chooses HashAgg based on
> costing. If false, it only generates a HashAgg path if it thinks it will fit
> in work_mem, similar to the old behavior (though it wlil now spill to disk if
> the planner was wrong about it fitting in work_mem).  The current default is
> true.

Are there any other GUCs that behave like that ?  It's confusing to me when I
see "Disk Usage: ... kB", despite setting it to "disable", and without the
usual disable_cost.  I realize that postgres chose the plan on the hypothesis
that it would *not* exceed work_mem, and that spilling to disk is considered
preferable to ignoring the setting, and that "going back" to planning phase
isn't a possibility.

template1=# explain (analyze, costs off, summary off) SELECT a, COUNT(1) FROM generate_series(1,999999) a GROUP BY 1 ;
 HashAggregate (actual time=1370.945..2877.250 rows=999999 loops=1)
   Group Key: a
   Peak Memory Usage: 5017 kB
   Disk Usage: 22992 kB
   HashAgg Batches: 84
   ->  Function Scan on generate_series a (actual time=314.507..741.517 rows=999999 loops=1)

A previous version of the docs said this, which I thought was confusing, and you removed it.
But I guess this is the behavior it was trying to .. explain.

+      <term><varname>enable_hashagg_disk</varname> (<type>boolean</type>)
+        ... This only affects the planner choice;
+        execution time may still require using disk-based hash
+        aggregation. The default is <literal>on</literal>.

I suggest that should be reworded and then re-introduced, unless there's some
further behavior change allowing the previous behavior of
might-exceed-work-mem.

"This setting determines whether the planner will elect to use a hash plan
which it expects will exceed work_mem and spill to disk.  During execution,
hash nodes which exceed work_mem will spill to disk even if this setting is
disabled.  To avoid spilling to disk, either increase work_mem (or set
enable_hashagg=off)."

For sure the release notes should recommend re-calibrating work_mem.

-- 
Justin





^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* Re: Default setting for enable_hashagg_disk
@ 2020-04-09 11:48  Tomas Vondra <tomas.vondra@2ndquadrant.com>
  parent: Justin Pryzby <pryzby@telsasoft.com>
  0 siblings, 2 replies; 275+ messages in thread

From: Tomas Vondra @ 2020-04-09 11:48 UTC (permalink / raw)
  To: Justin Pryzby <pryzby@telsasoft.com>; +Cc: Jeff Davis <pgsql@j-davis.com>; pgsql-hackers

On Tue, Apr 07, 2020 at 05:39:01PM -0500, Justin Pryzby wrote:
>On Tue, Apr 07, 2020 at 11:20:46AM -0700, Jeff Davis wrote:
>> The enable_hashagg_disk GUC, if set to true, chooses HashAgg based on
>> costing. If false, it only generates a HashAgg path if it thinks it will fit
>> in work_mem, similar to the old behavior (though it wlil now spill to disk if
>> the planner was wrong about it fitting in work_mem).  The current default is
>> true.
>
>Are there any other GUCs that behave like that ?  It's confusing to me when I
>see "Disk Usage: ... kB", despite setting it to "disable", and without the
>usual disable_cost.  I realize that postgres chose the plan on the hypothesis
>that it would *not* exceed work_mem, and that spilling to disk is considered
>preferable to ignoring the setting, and that "going back" to planning phase
>isn't a possibility.
>

It it really any different from our enable_* GUCs? Even if you do e.g.
enable_sort=off, we may still do a sort. Same for enable_groupagg etc.

>template1=# explain (analyze, costs off, summary off) SELECT a, COUNT(1) FROM generate_series(1,999999) a GROUP BY 1 ;
> HashAggregate (actual time=1370.945..2877.250 rows=999999 loops=1)
>   Group Key: a
>   Peak Memory Usage: 5017 kB
>   Disk Usage: 22992 kB
>   HashAgg Batches: 84
>   ->  Function Scan on generate_series a (actual time=314.507..741.517 rows=999999 loops=1)
>
>A previous version of the docs said this, which I thought was confusing, and you removed it.
>But I guess this is the behavior it was trying to .. explain.
>
>+      <term><varname>enable_hashagg_disk</varname> (<type>boolean</type>)
>+        ... This only affects the planner choice;
>+        execution time may still require using disk-based hash
>+        aggregation. The default is <literal>on</literal>.
>
>I suggest that should be reworded and then re-introduced, unless there's some
>further behavior change allowing the previous behavior of
>might-exceed-work-mem.
>

Yeah, it would be good to mention this is a best-effort setting.

>"This setting determines whether the planner will elect to use a hash plan
>which it expects will exceed work_mem and spill to disk.  During execution,
>hash nodes which exceed work_mem will spill to disk even if this setting is
>disabled.  To avoid spilling to disk, either increase work_mem (or set
>enable_hashagg=off)."
>
>For sure the release notes should recommend re-calibrating work_mem.
>

I don't follow. Why would the recalibrating be needed?

regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services





^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* Re: Default setting for enable_hashagg_disk
@ 2020-04-09 17:24  Justin Pryzby <pryzby@telsasoft.com>
  parent: Tomas Vondra <tomas.vondra@2ndquadrant.com>
  1 sibling, 1 reply; 275+ messages in thread

From: Justin Pryzby @ 2020-04-09 17:24 UTC (permalink / raw)
  To: Tomas Vondra <tomas.vondra@2ndquadrant.com>; +Cc: Jeff Davis <pgsql@j-davis.com>; pgsql-hackers

On Thu, Apr 09, 2020 at 01:48:55PM +0200, Tomas Vondra wrote:
> On Tue, Apr 07, 2020 at 05:39:01PM -0500, Justin Pryzby wrote:
> > On Tue, Apr 07, 2020 at 11:20:46AM -0700, Jeff Davis wrote:
> > > The enable_hashagg_disk GUC, if set to true, chooses HashAgg based on
> > > costing. If false, it only generates a HashAgg path if it thinks it will fit
> > > in work_mem, similar to the old behavior (though it wlil now spill to disk if
> > > the planner was wrong about it fitting in work_mem).  The current default is
> > > true.
> > 
> > Are there any other GUCs that behave like that ?  It's confusing to me when I
> > see "Disk Usage: ... kB", despite setting it to "disable", and without the
> > usual disable_cost.  I realize that postgres chose the plan on the hypothesis
> > that it would *not* exceed work_mem, and that spilling to disk is considered
> > preferable to ignoring the setting, and that "going back" to planning phase
> > isn't a possibility.
> 
> It it really any different from our enable_* GUCs? Even if you do e.g.
> enable_sort=off, we may still do a sort. Same for enable_groupagg etc.

Those show that the GUC was disabled by showing disable_cost.  That's what's
different about this one.

Also.. there's no such thing as enable_groupagg?  Unless I've been missing out
on something.

> > "This setting determines whether the planner will elect to use a hash plan
> > which it expects will exceed work_mem and spill to disk.  During execution,
> > hash nodes which exceed work_mem will spill to disk even if this setting is
> > disabled.  To avoid spilling to disk, either increase work_mem (or set
> > enable_hashagg=off)."
> > 
> > For sure the release notes should recommend re-calibrating work_mem.
> 
> I don't follow. Why would the recalibrating be needed?

Because HashAgg plans which used to run fine (because they weren't prevented
from overflowing work_mem) might now run poorly after spilling to disk (because
of overflowing work_mem).

-- 
Justin





^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* Re: Default setting for enable_hashagg_disk
@ 2020-04-09 18:25  Jeff Davis <pgsql@j-davis.com>
  parent: Justin Pryzby <pryzby@telsasoft.com>
  0 siblings, 0 replies; 275+ messages in thread

From: Jeff Davis @ 2020-04-09 18:25 UTC (permalink / raw)
  To: Justin Pryzby <pryzby@telsasoft.com>; Tomas Vondra <tomas.vondra@2ndquadrant.com>; +Cc: pgsql-hackers

On Thu, 2020-04-09 at 12:24 -0500, Justin Pryzby wrote:
> Also.. there's no such thing as enable_groupagg?  Unless I've been
> missing out
> on something.

I thought about adding that, and went so far as to make a patch. But it
didn't seem right to me -- the grouping isn't what takes the time, it's
the sorting. So what would the point of such a GUC be? To disable
GroupAgg when the input data is already sorted? Or a strange way to
disable Sort?

> Because HashAgg plans which used to run fine (because they weren't
> prevented
> from overflowing work_mem) might now run poorly after spilling to
> disk (because
> of overflowing work_mem).

It's probably worth a mention in the release notes, but I wouldn't word
it too strongly. Typically the performance difference is not a lot if
the workload still fits in system memory.

Regards,
	Jeff Davis







^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* Re: Default setting for enable_hashagg_disk
@ 2020-04-09 19:26  Robert Haas <robertmhaas@gmail.com>
  parent: Tomas Vondra <tomas.vondra@2ndquadrant.com>
  1 sibling, 1 reply; 275+ messages in thread

From: Robert Haas @ 2020-04-09 19:26 UTC (permalink / raw)
  To: Tomas Vondra <tomas.vondra@2ndquadrant.com>; +Cc: Justin Pryzby <pryzby@telsasoft.com>; Jeff Davis <pgsql@j-davis.com>; pgsql-hackers

On Thu, Apr 9, 2020 at 7:49 AM Tomas Vondra
<tomas.vondra@2ndquadrant.com> wrote:
> It it really any different from our enable_* GUCs? Even if you do e.g.
> enable_sort=off, we may still do a sort. Same for enable_groupagg etc.

I think it's actually pretty different. All of the other enable_* GUCs
disable an entire type of plan node, except for cases where that would
otherwise result in planning failure. This just disables a portion of
the planning logic for a certain kind of node, without actually
disabling the whole node type. I'm not sure that's a bad idea, but it
definitely seems to be inconsistent with what we've done in the past.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company





^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* Re: Default setting for enable_hashagg_disk
@ 2020-04-09 20:02  Jeff Davis <pgsql@j-davis.com>
  parent: Robert Haas <robertmhaas@gmail.com>
  0 siblings, 0 replies; 275+ messages in thread

From: Jeff Davis @ 2020-04-09 20:02 UTC (permalink / raw)
  To: Robert Haas <robertmhaas@gmail.com>; Tomas Vondra <tomas.vondra@2ndquadrant.com>; +Cc: Justin Pryzby <pryzby@telsasoft.com>; pgsql-hackers

On Thu, 2020-04-09 at 15:26 -0400, Robert Haas wrote:
> I think it's actually pretty different. All of the other enable_*
> GUCs
> disable an entire type of plan node, except for cases where that
> would
> otherwise result in planning failure. This just disables a portion of
> the planning logic for a certain kind of node, without actually
> disabling the whole node type. I'm not sure that's a bad idea, but it
> definitely seems to be inconsistent with what we've done in the past.

The patch adds two GUCs. Both are slightly weird, to be honest, but let
me explain the reasoning. I am open to other suggestions.

1. enable_hashagg_disk (default true):

This is essentially there just to get some of the old behavior back, to
give people an escape hatch if they see bad plans while we are tweaking
the costing. The old behavior was weird, so this GUC is also weird.

Perhaps we can make this a compatibility GUC that we eventually drop? I
don't necessarily think this GUC would make sense, say, 5 versions from
now. I'm just trying to be conservative because I know that, even if
the plans are faster for 90% of people, the other 10% will be unhappy
and want a way to work around it.

2. enable_groupingsets_hash_disk (default false):

This is about how we choose which grouping sets to hash and which to
sort when generating mixed mode paths.

Even before this patch, there are quite a few paths that could be
generated. It tries to estimate the size of each grouping set's hash
table, and then see how many it can fit in work_mem (knapsack), while
also taking advantage of any path keys, etc.

With Disk-based Hash Aggregation, in principle we can generate paths
representing any combination of hashing and sorting for the grouping
sets. But that would be overkill (and grow to a huge number of paths if
we have more than a handful of grouping sets). So I think the existing
planner logic for grouping sets is fine for now. We might come up with
a better approach later.

But that created a testing problem, because if the planner estimates
correctly, no hashed grouping sets will spill, and the spilling code
won't be exercised. This GUC makes the planner disregard which grouping
sets' hash tables will fit, making it much easier to exercise the
spilling code. Is there a better way I should be testing this code
path?

Regards,
	Jeff Davis







^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


--nextPart6784952.tM3a2QDmDi
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^ permalink  raw  reply  [nested|flat] 275+ messages in thread

* [PATCH v1 2/4] Introduce trenary reloptions
@ 2025-08-29 14:12  Nikolay Shaplov <dhyan@nataraj.su>
  0 siblings, 0 replies; 275+ messages in thread

From: Nikolay Shaplov @ 2025-08-29 14:12 UTC (permalink / raw)

Introduce trenary reloption as a replacement for current `vacuum_truncate`
implementation. Remove `vacuum_truncate_set` additional flag and using
`TRENARY_UNSET` value instead.
---
 src/backend/access/common/reloptions.c | 129 ++++++++++++++++++++-----
 src/backend/commands/vacuum.c          |   4 +-
 src/include/access/reloptions.h        |  26 ++---
 src/include/c.h                        |  16 +++
 src/include/utils/rel.h                |   3 +-
 5 files changed, 135 insertions(+), 43 deletions(-)

diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 0af3fea68fa..24662d277c8 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -40,9 +40,9 @@
  *
  * To add an option:
  *
- * (i) decide on a type (bool, integer, real, enum, string), name, default
- * value, upper and lower bounds (if applicable); for strings, consider a
- * validation routine.
+ * (i) decide on a type (bool, trenary, integer, real, enum, string), name,
+ * default value, upper and lower bounds (if applicable); for strings,
+ * consider a validation routine.
  * (ii) add a record below (or use add_<type>_reloption).
  * (iii) add it to the appropriate options struct (perhaps StdRdOptions)
  * (iv) add it to the appropriate handling routine (perhaps
@@ -147,15 +147,6 @@ static relopt_bool boolRelOpts[] =
 		},
 		false
 	},
-	{
-		{
-			"vacuum_truncate",
-			"Enables vacuum to truncate empty pages at the end of this table",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		true
-	},
 	{
 		{
 			"deduplicate_items",
@@ -170,6 +161,21 @@ static relopt_bool boolRelOpts[] =
 	{{NULL}}
 };
 
+static relopt_trenary trenaryRelOpts[] =
+{
+	{
+		{
+			"vacuum_truncate",
+			"Enables vacuum to truncate empty pages at the end of this table",
+			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+			ShareUpdateExclusiveLock
+		},
+		TRENARY_UNSET
+	},
+	/* list terminator */
+	{{NULL}}
+};
+
 static relopt_int intRelOpts[] =
 {
 	{
@@ -600,6 +606,13 @@ initialize_reloptions(void)
 								   boolRelOpts[i].gen.lockmode));
 		j++;
 	}
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		Assert(DoLockModesConflict(trenaryRelOpts[i].gen.lockmode,
+								   trenaryRelOpts[i].gen.lockmode));
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		Assert(DoLockModesConflict(intRelOpts[i].gen.lockmode,
@@ -640,6 +653,14 @@ initialize_reloptions(void)
 		j++;
 	}
 
+	for (i = 0; trenaryRelOpts[i].gen.name; i++)
+	{
+		relOpts[j] = &trenaryRelOpts[i].gen;
+		relOpts[j]->type = RELOPT_TYPE_TRENARY;
+		relOpts[j]->namelen = strlen(relOpts[j]->name);
+		j++;
+	}
+
 	for (i = 0; intRelOpts[i].gen.name; i++)
 	{
 		relOpts[j] = &intRelOpts[i].gen;
@@ -800,6 +821,9 @@ allocate_reloption(bits32 kinds, int type, const char *name, const char *desc,
 		case RELOPT_TYPE_BOOL:
 			size = sizeof(relopt_bool);
 			break;
+		case RELOPT_TYPE_TRENARY:
+			size = sizeof(relopt_trenary);
+			break;
 		case RELOPT_TYPE_INT:
 			size = sizeof(relopt_int);
 			break;
@@ -883,6 +907,54 @@ add_local_bool_reloption(local_relopts *relopts, const char *name,
 	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
 }
 
+/*
+ * init_trenary_reloption
+ *		Allocate and initialize a new trenary reloption
+ */
+static relopt_trenary *
+init_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+					trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption;
+
+	newoption = (relopt_trenary *) allocate_reloption(kinds,
+									RELOPT_TYPE_TRENARY, name, desc, lockmode);
+	newoption->default_val = default_val;
+
+	return newoption;
+}
+
+/*
+ * add_trenary_reloption
+ *		Add a new trenary reloption
+ */
+void
+add_trenary_reloption(bits32 kinds, const char *name, const char *desc,
+				   trenary default_val, LOCKMODE lockmode)
+{
+	relopt_trenary *newoption = init_trenary_reloption(kinds, name, desc,
+												 default_val, lockmode);
+
+	add_reloption((relopt_gen *) newoption);
+}
+
+/*
+ * add_local_trenary_reloption
+ *		Add a new trenary local reloption
+ *
+ * 'offset' is offset of trenary-typed field.
+ */
+void
+add_local_trenary_reloption(local_relopts *relopts, const char *name,
+							const char *desc, trenary default_val,
+							int offset)
+{
+	relopt_trenary *newoption = init_trenary_reloption(RELOPT_KIND_LOCAL,
+												name, desc,
+												default_val, 0);
+
+	add_local_reloption(relopts, (relopt_gen *) newoption, offset);
+}
 
 /*
  * init_real_reloption
@@ -1617,6 +1689,18 @@ parse_one_reloption(relopt_value *option, char *text_str, int text_len,
 									option->gen->name, value)));
 			}
 			break;
+		case RELOPT_TYPE_TRENARY:
+			{
+				bool b;
+				parsed = parse_bool(value, &b);
+				option->values.trenary_val = b ? TRENARY_TRUE : TRENARY_FALSE;
+				if (validate && !parsed)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("invalid value for trenary option \"%s\": %s",
+									option->gen->name, value)));
+			}
+			break;
 		case RELOPT_TYPE_INT:
 			{
 				relopt_int *optint = (relopt_int *) option->gen;
@@ -1780,17 +1864,6 @@ fillRelOptions(void *rdopts, Size basesize,
 				char	   *itempos = ((char *) rdopts) + elems[j].offset;
 				char	   *string_val;
 
-				/*
-				 * If isset_offset is provided, store whether the reloption is
-				 * set there.
-				 */
-				if (elems[j].isset_offset > 0)
-				{
-					char	   *setpos = ((char *) rdopts) + elems[j].isset_offset;
-
-					*(bool *) setpos = options[i].isset;
-				}
-
 				switch (options[i].gen->type)
 				{
 					case RELOPT_TYPE_BOOL:
@@ -1798,6 +1871,11 @@ fillRelOptions(void *rdopts, Size basesize,
 							options[i].values.bool_val :
 							((relopt_bool *) options[i].gen)->default_val;
 						break;
+					case RELOPT_TYPE_TRENARY:
+						*(trenary *) itempos = options[i].isset ?
+							options[i].values.trenary_val :
+							((relopt_trenary *) options[i].gen)->default_val;
+						break;
 					case RELOPT_TYPE_INT:
 						*(int *) itempos = options[i].isset ?
 							options[i].values.int_val :
@@ -1912,8 +1990,8 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, parallel_workers)},
 		{"vacuum_index_cleanup", RELOPT_TYPE_ENUM,
 		offsetof(StdRdOptions, vacuum_index_cleanup)},
-		{"vacuum_truncate", RELOPT_TYPE_BOOL,
-		offsetof(StdRdOptions, vacuum_truncate), offsetof(StdRdOptions, vacuum_truncate_set)},
+		{"vacuum_truncate", RELOPT_TYPE_TRENARY,
+		offsetof(StdRdOptions, vacuum_truncate)},
 		{"vacuum_max_eager_freeze_failure_rate", RELOPT_TYPE_REAL,
 		offsetof(StdRdOptions, vacuum_max_eager_freeze_failure_rate)}
 	};
@@ -1993,7 +2071,6 @@ build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
 		elems[i].optname = opt->option->name;
 		elems[i].opttype = opt->option->type;
 		elems[i].offset = opt->offset;
-		elems[i].isset_offset = 0;	/* not supported for local relopts yet */
 
 		i++;
 	}
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 733ef40ae7c..7b96c7f9a80 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2221,9 +2221,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
-		if (opts && opts->vacuum_truncate_set)
+		if (opts && opts->vacuum_truncate != TRENARY_UNSET)
 		{
-			if (opts->vacuum_truncate)
+			if (opts->vacuum_truncate == TRENARY_TRUE)
 				params.truncate = VACOPTVALUE_ENABLED;
 			else
 				params.truncate = VACOPTVALUE_DISABLED;
diff --git a/src/include/access/reloptions.h b/src/include/access/reloptions.h
index a604a4702c3..1a6717ed213 100644
--- a/src/include/access/reloptions.h
+++ b/src/include/access/reloptions.h
@@ -29,6 +29,7 @@
 typedef enum relopt_type
 {
 	RELOPT_TYPE_BOOL,
+	RELOPT_TYPE_TRENARY,  /* on, off, unset */
 	RELOPT_TYPE_INT,
 	RELOPT_TYPE_REAL,
 	RELOPT_TYPE_ENUM,
@@ -80,6 +81,7 @@ typedef struct relopt_value
 	union
 	{
 		bool		bool_val;
+		trenary		trenary_val;
 		int			int_val;
 		double		real_val;
 		int			enum_val;
@@ -94,6 +96,12 @@ typedef struct relopt_bool
 	bool		default_val;
 } relopt_bool;
 
+typedef struct relopt_rernary
+{
+	relopt_gen	gen;
+	int 		default_val;
+} relopt_trenary;
+
 typedef struct relopt_int
 {
 	relopt_gen	gen;
@@ -152,19 +160,6 @@ typedef struct
 	const char *optname;		/* option's name */
 	relopt_type opttype;		/* option's datatype */
 	int			offset;			/* offset of field in result struct */
-
-	/*
-	 * isset_offset is an optional offset of a field in the result struct that
-	 * stores whether the option is explicitly set for the relation or if it
-	 * just picked up the default value.  In most cases, this can be
-	 * accomplished by giving the reloption a special out-of-range default
-	 * value (e.g., some integer reloptions use -2), but this isn't always
-	 * possible.  For example, a Boolean reloption cannot be given an
-	 * out-of-range default, so we need another way to discover the source of
-	 * its value.  This offset is only used if given a value greater than
-	 * zero.
-	 */
-	int			isset_offset;
 } relopt_parse_elt;
 
 /* Local reloption definition */
@@ -195,6 +190,8 @@ typedef struct local_relopts
 extern relopt_kind add_reloption_kind(void);
 extern void add_bool_reloption(bits32 kinds, const char *name, const char *desc,
 							   bool default_val, LOCKMODE lockmode);
+extern void add_trenary_reloption(bits32 kinds, const char *name,
+					const char *desc, int default_val, LOCKMODE lockmode);
 extern void add_int_reloption(bits32 kinds, const char *name, const char *desc,
 							  int default_val, int min_val, int max_val,
 							  LOCKMODE lockmode);
@@ -214,6 +211,9 @@ extern void register_reloptions_validator(local_relopts *relopts,
 extern void add_local_bool_reloption(local_relopts *relopts, const char *name,
 									 const char *desc, bool default_val,
 									 int offset);
+extern void add_local_trenary_reloption(local_relopts *relopts,
+								const char *name, const char *desc,
+								trenary default_val, int offset);
 extern void add_local_int_reloption(local_relopts *relopts, const char *name,
 									const char *desc, int default_val,
 									int min_val, int max_val, int offset);
diff --git a/src/include/c.h b/src/include/c.h
index 39022f8a9dd..dec390c1e77 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -488,6 +488,22 @@ typedef void (*pg_funcptr_t) (void);
 
 #include <stdbool.h>
 
+/*
+ * trenary
+ *		Boolean value with an extrea "unset" option
+ *
+ * Trenary data type is used in relation options that can be "true", "false" or
+ * "unset". Since relation options are used deep inside the PostgreSQL code,
+ * this type is declared globally.
+*/
+
+typedef enum trenary
+{
+	TRENARY_FALSE = 0,
+	TRENARY_TRUE = 1,
+	TRENARY_UNSET = -1
+} trenary;
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	standard system types
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b552359915f..08f93bde007 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -346,8 +346,7 @@ typedef struct StdRdOptions
 	bool		user_catalog_table; /* use as an additional catalog relation */
 	int			parallel_workers;	/* max number of parallel workers */
 	StdRdOptIndexCleanup vacuum_index_cleanup;	/* controls index vacuuming */
-	bool		vacuum_truncate;	/* enables vacuum to truncate a relation */
-	bool		vacuum_truncate_set;	/* whether vacuum_truncate is set */
+	trenary		vacuum_truncate;	/* enables vacuum to truncate a relation */
 
 	/*
 	 * Fraction of pages in a relation that vacuum can eagerly scan and fail
-- 
2.39.2


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