[Peter Eisentraut <peter.eisentraut@2ndquadrant.com>]

In [0] it was discussed that hash support for row types/record would be 
handy.  So I implemented that.

The implementation hashes each field and combines the hash values.  Most 
of the code structure can be borrowed from the record comparison 
functions/btree support.  To combine the hash values, I adapted the code 
from the array hashing functions.  (The hash_combine()/hash_combine64() 
functions also looked sensible, but they don't appear to work in a way 
that satisfies the hash_func regression test.  Could be documented better.)

The main motivation is to support UNION [DISTINCT] as discussed in [0], 
but this also enables other hash-related functionality such as hash 
joins (as one regression test accidentally revealed) and hash partitioning.


[0]: 
https://www.postgresql.org/message-id/flat/52beaf44-ccc3-0ba1-45c7-74aa251cd6ab%402ndquadrant.com#95...

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
From 3c9269d60abc5033804802713d9a10f72e77f3e0 Mon Sep 17 00:00:00 2001
From: Peter Eisentraut <peter@eisentraut.org>
Date: Mon, 19 Oct 2020 09:44:15 +0200
Subject: [PATCH v1] Hash support for row types

Add hash functions for the record type as well as a hash operator
family and operator class for the record type.  This enables all the
hash functionality for the record type such as UNION DISTINCT, hash
joins, and hash partitioning.
---
 doc/src/sgml/queries.sgml               |   9 -
 src/backend/utils/adt/rowtypes.c        | 249 ++++++++++++++++++++++++
 src/include/catalog/pg_amop.dat         |   5 +
 src/include/catalog/pg_amproc.dat       |   4 +
 src/include/catalog/pg_opclass.dat      |   2 +
 src/include/catalog/pg_operator.dat     |   2 +-
 src/include/catalog/pg_opfamily.dat     |   2 +
 src/include/catalog/pg_proc.dat         |   7 +
 src/test/regress/expected/hash_func.out |  12 ++
 src/test/regress/expected/join.out      |   1 +
 src/test/regress/expected/with.out      |  38 ++++
 src/test/regress/sql/hash_func.sql      |   9 +
 src/test/regress/sql/join.sql           |   1 +
 src/test/regress/sql/with.sql           |  10 +
 14 files changed, 341 insertions(+), 10 deletions(-)

diff --git a/doc/src/sgml/queries.sgml b/doc/src/sgml/queries.sgml
index f06afe2c3f..8e70e57b72 100644
--- a/doc/src/sgml/queries.sgml
+++ b/doc/src/sgml/queries.sgml
@@ -2182,15 +2182,6 @@ <title>Search Order</title>
 </programlisting>
    </para>
 
-   <note>
-    <para>
-     The queries shown in this and the following section involving
-     <literal>ROW</literal> constructors in the target list only support
-     <literal>UNION ALL</literal> (not plain <literal>UNION</literal>) in the
-     current implementation.
-    </para>
-   </note>
-
    <tip>
     <para>
      Omit the <literal>ROW()</literal> syntax in the common case where only one
diff --git a/src/backend/utils/adt/rowtypes.c b/src/backend/utils/adt/rowtypes.c
index 674cf0a55d..5c86259929 100644
--- a/src/backend/utils/adt/rowtypes.c
+++ b/src/backend/utils/adt/rowtypes.c
@@ -19,6 +19,7 @@
 #include "access/detoast.h"
 #include "access/htup_details.h"
 #include "catalog/pg_type.h"
+#include "common/hashfn.h"
 #include "funcapi.h"
 #include "libpq/pqformat.h"
 #include "miscadmin.h"
@@ -1766,3 +1767,251 @@ btrecordimagecmp(PG_FUNCTION_ARGS)
 {
 	PG_RETURN_INT32(record_image_cmp(fcinfo));
 }
+
+
+/*
+ * Row type hash functions
+ */
+
+Datum
+record_hash(PG_FUNCTION_ARGS)
+{
+	HeapTupleHeader record = PG_GETARG_HEAPTUPLEHEADER(0);
+	uint32		result = 0;
+	Oid			tupType;
+	int32		tupTypmod;
+	TupleDesc	tupdesc;
+	HeapTupleData tuple;
+	int			ncolumns;
+	RecordCompareData *my_extra;
+	Datum	   *values;
+	bool	   *nulls;
+
+	check_stack_depth();		/* recurses for record-type columns */
+
+	/* Extract type info from tuple */
+	tupType = HeapTupleHeaderGetTypeId(record);
+	tupTypmod = HeapTupleHeaderGetTypMod(record);
+	tupdesc = lookup_rowtype_tupdesc(tupType, tupTypmod);
+	ncolumns = tupdesc->natts;
+
+	/* Build temporary HeapTuple control structure */
+	tuple.t_len = HeapTupleHeaderGetDatumLength(record);
+	ItemPointerSetInvalid(&(tuple.t_self));
+	tuple.t_tableOid = InvalidOid;
+	tuple.t_data = record;
+
+	/*
+	 * We arrange to look up the needed hashing info just once per series
+	 * of calls, assuming the record type doesn't change underneath us.
+	 */
+	my_extra = (RecordCompareData *) fcinfo->flinfo->fn_extra;
+	if (my_extra == NULL ||
+		my_extra->ncolumns < ncolumns)
+	{
+		fcinfo->flinfo->fn_extra =
+			MemoryContextAlloc(fcinfo->flinfo->fn_mcxt,
+							   offsetof(RecordCompareData, columns) +
+							   ncolumns * sizeof(ColumnCompareData));
+		my_extra = (RecordCompareData *) fcinfo->flinfo->fn_extra;
+		my_extra->ncolumns = ncolumns;
+		my_extra->record1_type = InvalidOid;
+		my_extra->record1_typmod = 0;
+	}
+
+	if (my_extra->record1_type != tupType ||
+		my_extra->record1_typmod != tupTypmod)
+	{
+		MemSet(my_extra->columns, 0, ncolumns * sizeof(ColumnCompareData));
+		my_extra->record1_type = tupType;
+		my_extra->record1_typmod = tupTypmod;
+	}
+
+	/* Break down the tuple into fields */
+	values = (Datum *) palloc(ncolumns * sizeof(Datum));
+	nulls = (bool *) palloc(ncolumns * sizeof(bool));
+	heap_deform_tuple(&tuple, tupdesc, values, nulls);
+
+	for (int i = 0; i < ncolumns; i++)
+	{
+		Form_pg_attribute att;
+		TypeCacheEntry *typentry;
+		uint32		element_hash;
+
+		att = TupleDescAttr(tupdesc, i);
+
+		if (att->attisdropped)
+			continue;
+
+		/*
+		 * Lookup the hash function if not done already
+		 */
+		typentry = my_extra->columns[i].typentry;
+		if (typentry == NULL ||
+			typentry->type_id != att->atttypid)
+		{
+			typentry = lookup_type_cache(att->atttypid,
+										 TYPECACHE_HASH_PROC_FINFO);
+			if (!OidIsValid(typentry->hash_proc_finfo.fn_oid))
+				ereport(ERROR,
+						(errcode(ERRCODE_UNDEFINED_FUNCTION),
+						 errmsg("could not identify a hash function for type %s",
+								format_type_be(typentry->type_id))));
+			my_extra->columns[i].typentry = typentry;
+		}
+
+		/* Compute hash of element */
+		if (nulls[i])
+		{
+			element_hash = 0;
+		}
+		else
+		{
+			LOCAL_FCINFO(locfcinfo, 1);
+
+			InitFunctionCallInfoData(*locfcinfo, &typentry->hash_proc_finfo, 1,
+									 att->attcollation, NULL, NULL);
+			locfcinfo->args[0].value = values[i];
+			locfcinfo->args[0].isnull = false;
+			element_hash = DatumGetUInt32(FunctionCallInvoke(locfcinfo));
+
+			/* We don't expect hash support functions to return null */
+			Assert(!locfcinfo->isnull);
+		}
+
+		/* see hash_array() */
+		result = (result << 5) - result + element_hash;
+	}
+
+	pfree(values);
+	pfree(nulls);
+	ReleaseTupleDesc(tupdesc);
+
+	/* Avoid leaking memory when handed toasted input. */
+	PG_FREE_IF_COPY(record, 0);
+
+	PG_RETURN_UINT32(result);
+}
+
+Datum
+record_hash_extended(PG_FUNCTION_ARGS)
+{
+	HeapTupleHeader record = PG_GETARG_HEAPTUPLEHEADER(0);
+	uint64		seed = PG_GETARG_INT64(1);
+	uint64		result = 0;
+	Oid			tupType;
+	int32		tupTypmod;
+	TupleDesc	tupdesc;
+	HeapTupleData tuple;
+	int			ncolumns;
+	RecordCompareData *my_extra;
+	Datum	   *values;
+	bool	   *nulls;
+
+	check_stack_depth();		/* recurses for record-type columns */
+
+	/* Extract type info from tuple */
+	tupType = HeapTupleHeaderGetTypeId(record);
+	tupTypmod = HeapTupleHeaderGetTypMod(record);
+	tupdesc = lookup_rowtype_tupdesc(tupType, tupTypmod);
+	ncolumns = tupdesc->natts;
+
+	/* Build temporary HeapTuple control structure */
+	tuple.t_len = HeapTupleHeaderGetDatumLength(record);
+	ItemPointerSetInvalid(&(tuple.t_self));
+	tuple.t_tableOid = InvalidOid;
+	tuple.t_data = record;
+
+	/*
+	 * We arrange to look up the needed hashing info just once per series
+	 * of calls, assuming the record type doesn't change underneath us.
+	 */
+	my_extra = (RecordCompareData *) fcinfo->flinfo->fn_extra;
+	if (my_extra == NULL ||
+		my_extra->ncolumns < ncolumns)
+	{
+		fcinfo->flinfo->fn_extra =
+			MemoryContextAlloc(fcinfo->flinfo->fn_mcxt,
+							   offsetof(RecordCompareData, columns) +
+							   ncolumns * sizeof(ColumnCompareData));
+		my_extra = (RecordCompareData *) fcinfo->flinfo->fn_extra;
+		my_extra->ncolumns = ncolumns;
+		my_extra->record1_type = InvalidOid;
+		my_extra->record1_typmod = 0;
+	}
+
+	if (my_extra->record1_type != tupType ||
+		my_extra->record1_typmod != tupTypmod)
+	{
+		MemSet(my_extra->columns, 0, ncolumns * sizeof(ColumnCompareData));
+		my_extra->record1_type = tupType;
+		my_extra->record1_typmod = tupTypmod;
+	}
+
+	/* Break down the tuple into fields */
+	values = (Datum *) palloc(ncolumns * sizeof(Datum));
+	nulls = (bool *) palloc(ncolumns * sizeof(bool));
+	heap_deform_tuple(&tuple, tupdesc, values, nulls);
+
+	for (int i = 0; i < ncolumns; i++)
+	{
+		Form_pg_attribute att;
+		TypeCacheEntry *typentry;
+		uint64		element_hash;
+
+		att = TupleDescAttr(tupdesc, i);
+
+		if (att->attisdropped)
+			continue;
+
+		/*
+		 * Lookup the hash function if not done already
+		 */
+		typentry = my_extra->columns[i].typentry;
+		if (typentry == NULL ||
+			typentry->type_id != att->atttypid)
+		{
+			typentry = lookup_type_cache(att->atttypid,
+										 TYPECACHE_HASH_EXTENDED_PROC_FINFO);
+			if (!OidIsValid(typentry->hash_extended_proc_finfo.fn_oid))
+				ereport(ERROR,
+						(errcode(ERRCODE_UNDEFINED_FUNCTION),
+						 errmsg("could not identify a hash function for type %s",
+								format_type_be(typentry->type_id))));
+			my_extra->columns[i].typentry = typentry;
+		}
+
+		/* Compute hash of element */
+		if (nulls[i])
+		{
+			element_hash = 0;
+		}
+		else
+		{
+			LOCAL_FCINFO(locfcinfo, 2);
+
+			InitFunctionCallInfoData(*locfcinfo, &typentry->hash_extended_proc_finfo, 2,
+									 att->attcollation, NULL, NULL);
+			locfcinfo->args[0].value = values[i];
+			locfcinfo->args[0].isnull = false;
+			locfcinfo->args[1].value = Int64GetDatum(seed);
+			locfcinfo->args[0].isnull = false;
+			element_hash = DatumGetUInt64(FunctionCallInvoke(locfcinfo));
+
+			/* We don't expect hash support functions to return null */
+			Assert(!locfcinfo->isnull);
+		}
+
+		/* see hash_array_extended() */
+		result = (result << 5) - result + element_hash;
+	}
+
+	pfree(values);
+	pfree(nulls);
+	ReleaseTupleDesc(tupdesc);
+
+	/* Avoid leaking memory when handed toasted input. */
+	PG_FREE_IF_COPY(record, 0);
+
+	PG_RETURN_UINT64(result);
+}
diff --git a/src/include/catalog/pg_amop.dat b/src/include/catalog/pg_amop.dat
index 1dfb6fd373..dccbeabcf4 100644
--- a/src/include/catalog/pg_amop.dat
+++ b/src/include/catalog/pg_amop.dat
@@ -979,6 +979,11 @@
   amoprighttype => 'oidvector', amopstrategy => '1',
   amopopr => '=(oidvector,oidvector)', amopmethod => 'hash' },
 
+# record_ops
+{ amopfamily => 'hash/record_ops', amoplefttype => 'record',
+  amoprighttype => 'record', amopstrategy => '1',
+  amopopr => '=(record,record)', amopmethod => 'hash' },
+
 # text_ops
 { amopfamily => 'hash/text_ops', amoplefttype => 'text',
   amoprighttype => 'text', amopstrategy => '1', amopopr => '=(text,text)',
diff --git a/src/include/catalog/pg_amproc.dat b/src/include/catalog/pg_amproc.dat
index a8e0c4ff8a..e000421788 100644
--- a/src/include/catalog/pg_amproc.dat
+++ b/src/include/catalog/pg_amproc.dat
@@ -433,6 +433,10 @@
   amprocrighttype => 'uuid', amprocnum => '1', amproc => 'uuid_hash' },
 { amprocfamily => 'hash/uuid_ops', amproclefttype => 'uuid',
   amprocrighttype => 'uuid', amprocnum => '2', amproc => 'uuid_hash_extended' },
+{ amprocfamily => 'hash/record_ops', amproclefttype => 'record',
+  amprocrighttype => 'record', amprocnum => '1', amproc => 'record_hash' },
+{ amprocfamily => 'hash/record_ops', amproclefttype => 'record',
+  amprocrighttype => 'record', amprocnum => '2', amproc => 'record_hash_extended' },
 { amprocfamily => 'hash/pg_lsn_ops', amproclefttype => 'pg_lsn',
   amprocrighttype => 'pg_lsn', amprocnum => '1', amproc => 'pg_lsn_hash' },
 { amprocfamily => 'hash/pg_lsn_ops', amproclefttype => 'pg_lsn',
diff --git a/src/include/catalog/pg_opclass.dat b/src/include/catalog/pg_opclass.dat
index f2342bb328..be5712692f 100644
--- a/src/include/catalog/pg_opclass.dat
+++ b/src/include/catalog/pg_opclass.dat
@@ -114,6 +114,8 @@
   opcfamily => 'hash/oidvector_ops', opcintype => 'oidvector' },
 { opcmethod => 'btree', opcname => 'record_ops',
   opcfamily => 'btree/record_ops', opcintype => 'record' },
+{ opcmethod => 'hash', opcname => 'record_ops',
+  opcfamily => 'hash/record_ops', opcintype => 'record' },
 { opcmethod => 'btree', opcname => 'record_image_ops',
   opcfamily => 'btree/record_image_ops', opcintype => 'record',
   opcdefault => 'f' },
diff --git a/src/include/catalog/pg_operator.dat b/src/include/catalog/pg_operator.dat
index 7cc812adda..1ffd826679 100644
--- a/src/include/catalog/pg_operator.dat
+++ b/src/include/catalog/pg_operator.dat
@@ -3064,7 +3064,7 @@
 
 # generic record comparison operators
 { oid => '2988', oid_symbol => 'RECORD_EQ_OP', descr => 'equal',
-  oprname => '=', oprcanmerge => 't', oprleft => 'record', oprright => 'record',
+  oprname => '=', oprcanmerge => 't', oprcanhash => 't', oprleft => 'record', oprright => 'record',
   oprresult => 'bool', oprcom => '=(record,record)',
   oprnegate => '<>(record,record)', oprcode => 'record_eq', oprrest => 'eqsel',
   oprjoin => 'eqjoinsel' },
diff --git a/src/include/catalog/pg_opfamily.dat b/src/include/catalog/pg_opfamily.dat
index cf0fb325b3..11c7ad2c14 100644
--- a/src/include/catalog/pg_opfamily.dat
+++ b/src/include/catalog/pg_opfamily.dat
@@ -76,6 +76,8 @@
   opfmethod => 'hash', opfname => 'oidvector_ops' },
 { oid => '2994',
   opfmethod => 'btree', opfname => 'record_ops' },
+{ oid => '9611',
+  opfmethod => 'hash', opfname => 'record_ops' },
 { oid => '3194',
   opfmethod => 'btree', opfname => 'record_image_ops' },
 { oid => '1994', oid_symbol => 'TEXT_BTREE_FAM_OID',
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 22340baf1c..1d113272fd 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -9670,6 +9670,13 @@
   proname => 'btrecordcmp', prorettype => 'int4',
   proargtypes => 'record record', prosrc => 'btrecordcmp' },
 
+{ oid => '9609', descr => 'hash',
+  proname => 'record_hash', prorettype => 'int4', proargtypes => 'record',
+  prosrc => 'record_hash' },
+{ oid => '9610', descr => 'hash',
+  proname => 'record_hash_extended', prorettype => 'int8', proargtypes => 'record int8',
+  prosrc => 'record_hash_extended' },
+
 # record comparison using raw byte images
 { oid => '3181',
   proname => 'record_image_eq', prorettype => 'bool',
diff --git a/src/test/regress/expected/hash_func.out b/src/test/regress/expected/hash_func.out
index e6e3410aaa..9c11e16b0b 100644
--- a/src/test/regress/expected/hash_func.out
+++ b/src/test/regress/expected/hash_func.out
@@ -298,3 +298,15 @@ WHERE  hash_range(v)::bit(32) != hash_range_extended(v, 0)::bit(32)
 -------+----------+-----------+-----------
 (0 rows)
 
+CREATE TYPE t1 AS (a int, b text);
+SELECT v as value, record_hash(v)::bit(32) as standard,
+       record_hash_extended(v, 0)::bit(32) as extended0,
+       record_hash_extended(v, 1)::bit(32) as extended1
+FROM   (VALUES (row(1, 'aaa')::t1, row(2, 'bbb'), row(-1, 'ccc'))) x(v)
+WHERE  record_hash(v)::bit(32) != record_hash_extended(v, 0)::bit(32)
+       OR record_hash(v)::bit(32) = record_hash_extended(v, 1)::bit(32);
+ value | standard | extended0 | extended1 
+-------+----------+-----------+-----------
+(0 rows)
+
+DROP TYPE t1;
diff --git a/src/test/regress/expected/join.out b/src/test/regress/expected/join.out
index a46b1573bd..4a375deff3 100644
--- a/src/test/regress/expected/join.out
+++ b/src/test/regress/expected/join.out
@@ -2707,6 +2707,7 @@ select a.idv, b.idv from tidv a, tidv b where a.idv = b.idv;
 (5 rows)
 
 set enable_mergejoin = 0;
+set enable_hashjoin = 0;
 explain (costs off)
 select a.idv, b.idv from tidv a, tidv b where a.idv = b.idv;
                      QUERY PLAN                     
diff --git a/src/test/regress/expected/with.out b/src/test/regress/expected/with.out
index 457f3bf04f..6a01ddfdd6 100644
--- a/src/test/regress/expected/with.out
+++ b/src/test/regress/expected/with.out
@@ -616,6 +616,44 @@ select * from search_graph;
  2 | 3 | arc 2 -> 3 | f        | {"(1,4)","(4,5)","(5,1)","(1,2)","(2,3)"}
 (25 rows)
 
+-- again with union distinct to test row-type hash support
+with recursive search_graph(f, t, label, is_cycle, path) as (
+	select *, false, array[row(g.f, g.t)] from graph g
+	union distinct
+	select g.*, row(g.f, g.t) = any(path), path || row(g.f, g.t)
+	from graph g, search_graph sg
+	where g.f = sg.t and not is_cycle
+)
+select * from search_graph;
+ f | t |   label    | is_cycle |                   path                    
+---+---+------------+----------+-------------------------------------------
+ 1 | 2 | arc 1 -> 2 | f        | {"(1,2)"}
+ 1 | 3 | arc 1 -> 3 | f        | {"(1,3)"}
+ 2 | 3 | arc 2 -> 3 | f        | {"(2,3)"}
+ 1 | 4 | arc 1 -> 4 | f        | {"(1,4)"}
+ 4 | 5 | arc 4 -> 5 | f        | {"(4,5)"}
+ 5 | 1 | arc 5 -> 1 | f        | {"(5,1)"}
+ 1 | 2 | arc 1 -> 2 | f        | {"(5,1)","(1,2)"}
+ 1 | 3 | arc 1 -> 3 | f        | {"(5,1)","(1,3)"}
+ 1 | 4 | arc 1 -> 4 | f        | {"(5,1)","(1,4)"}
+ 2 | 3 | arc 2 -> 3 | f        | {"(1,2)","(2,3)"}
+ 4 | 5 | arc 4 -> 5 | f        | {"(1,4)","(4,5)"}
+ 5 | 1 | arc 5 -> 1 | f        | {"(4,5)","(5,1)"}
+ 1 | 2 | arc 1 -> 2 | f        | {"(4,5)","(5,1)","(1,2)"}
+ 1 | 3 | arc 1 -> 3 | f        | {"(4,5)","(5,1)","(1,3)"}
+ 1 | 4 | arc 1 -> 4 | f        | {"(4,5)","(5,1)","(1,4)"}
+ 2 | 3 | arc 2 -> 3 | f        | {"(5,1)","(1,2)","(2,3)"}
+ 4 | 5 | arc 4 -> 5 | f        | {"(5,1)","(1,4)","(4,5)"}
+ 5 | 1 | arc 5 -> 1 | f        | {"(1,4)","(4,5)","(5,1)"}
+ 1 | 2 | arc 1 -> 2 | f        | {"(1,4)","(4,5)","(5,1)","(1,2)"}
+ 1 | 3 | arc 1 -> 3 | f        | {"(1,4)","(4,5)","(5,1)","(1,3)"}
+ 1 | 4 | arc 1 -> 4 | t        | {"(1,4)","(4,5)","(5,1)","(1,4)"}
+ 2 | 3 | arc 2 -> 3 | f        | {"(4,5)","(5,1)","(1,2)","(2,3)"}
+ 4 | 5 | arc 4 -> 5 | t        | {"(4,5)","(5,1)","(1,4)","(4,5)"}
+ 5 | 1 | arc 5 -> 1 | t        | {"(5,1)","(1,4)","(4,5)","(5,1)"}
+ 2 | 3 | arc 2 -> 3 | f        | {"(1,4)","(4,5)","(5,1)","(1,2)","(2,3)"}
+(25 rows)
+
 -- ordering by the path column has same effect as SEARCH DEPTH FIRST
 with recursive search_graph(f, t, label, is_cycle, path) as (
 	select *, false, array[row(g.f, g.t)] from graph g
diff --git a/src/test/regress/sql/hash_func.sql b/src/test/regress/sql/hash_func.sql
index a3e2decc2c..747c79b915 100644
--- a/src/test/regress/sql/hash_func.sql
+++ b/src/test/regress/sql/hash_func.sql
@@ -220,3 +220,12 @@ CREATE TYPE mood AS ENUM ('sad', 'ok', 'happy');
         (int4range(550274, 1550274)), (int4range(1550275, 208112489))) x(v)
 WHERE  hash_range(v)::bit(32) != hash_range_extended(v, 0)::bit(32)
        OR hash_range(v)::bit(32) = hash_range_extended(v, 1)::bit(32);
+
+CREATE TYPE t1 AS (a int, b text);
+SELECT v as value, record_hash(v)::bit(32) as standard,
+       record_hash_extended(v, 0)::bit(32) as extended0,
+       record_hash_extended(v, 1)::bit(32) as extended1
+FROM   (VALUES (row(1, 'aaa')::t1, row(2, 'bbb'), row(-1, 'ccc'))) x(v)
+WHERE  record_hash(v)::bit(32) != record_hash_extended(v, 0)::bit(32)
+       OR record_hash(v)::bit(32) = record_hash_extended(v, 1)::bit(32);
+DROP TYPE t1;
diff --git a/src/test/regress/sql/join.sql b/src/test/regress/sql/join.sql
index 1403e0ffe7..023290bd52 100644
--- a/src/test/regress/sql/join.sql
+++ b/src/test/regress/sql/join.sql
@@ -700,6 +700,7 @@ CREATE TEMP TABLE tt2 ( tt2_id int4, joincol int4 );
 select a.idv, b.idv from tidv a, tidv b where a.idv = b.idv;
 
 set enable_mergejoin = 0;
+set enable_hashjoin = 0;
 
 explain (costs off)
 select a.idv, b.idv from tidv a, tidv b where a.idv = b.idv;
diff --git a/src/test/regress/sql/with.sql b/src/test/regress/sql/with.sql
index 2eea297a71..7aa164b997 100644
--- a/src/test/regress/sql/with.sql
+++ b/src/test/regress/sql/with.sql
@@ -317,6 +317,16 @@ CREATE TEMPORARY TABLE tree(
 )
 select * from search_graph;
 
+-- again with union distinct to test row-type hash support
+with recursive search_graph(f, t, label, is_cycle, path) as (
+	select *, false, array[row(g.f, g.t)] from graph g
+	union distinct
+	select g.*, row(g.f, g.t) = any(path), path || row(g.f, g.t)
+	from graph g, search_graph sg
+	where g.f = sg.t and not is_cycle
+)
+select * from search_graph;
+
 -- ordering by the path column has same effect as SEARCH DEPTH FIRST
 with recursive search_graph(f, t, label, is_cycle, path) as (
 	select *, false, array[row(g.f, g.t)] from graph g
-- 
2.28.0



Attachments:

  [text/plain] v1-0001-Hash-support-for-row-types.patch (19.2K, ../38eccd35-4e2d-6767-1b3c-dada1eac3124@2ndquadrant.com/2-v1-0001-Hash-support-for-row-types.patch)
  download | inline diff:
From 3c9269d60abc5033804802713d9a10f72e77f3e0 Mon Sep 17 00:00:00 2001
From: Peter Eisentraut <peter@eisentraut.org>
Date: Mon, 19 Oct 2020 09:44:15 +0200
Subject: [PATCH v1] Hash support for row types

Add hash functions for the record type as well as a hash operator
family and operator class for the record type.  This enables all the
hash functionality for the record type such as UNION DISTINCT, hash
joins, and hash partitioning.
---
 doc/src/sgml/queries.sgml               |   9 -
 src/backend/utils/adt/rowtypes.c        | 249 ++++++++++++++++++++++++
 src/include/catalog/pg_amop.dat         |   5 +
 src/include/catalog/pg_amproc.dat       |   4 +
 src/include/catalog/pg_opclass.dat      |   2 +
 src/include/catalog/pg_operator.dat     |   2 +-
 src/include/catalog/pg_opfamily.dat     |   2 +
 src/include/catalog/pg_proc.dat         |   7 +
 src/test/regress/expected/hash_func.out |  12 ++
 src/test/regress/expected/join.out      |   1 +
 src/test/regress/expected/with.out      |  38 ++++
 src/test/regress/sql/hash_func.sql      |   9 +
 src/test/regress/sql/join.sql           |   1 +
 src/test/regress/sql/with.sql           |  10 +
 14 files changed, 341 insertions(+), 10 deletions(-)

diff --git a/doc/src/sgml/queries.sgml b/doc/src/sgml/queries.sgml
index f06afe2c3f..8e70e57b72 100644
--- a/doc/src/sgml/queries.sgml
+++ b/doc/src/sgml/queries.sgml
@@ -2182,15 +2182,6 @@ <title>Search Order</title>
 </programlisting>
    </para>
 
-   <note>
-    <para>
-     The queries shown in this and the following section involving
-     <literal>ROW</literal> constructors in the target list only support
-     <literal>UNION ALL</literal> (not plain <literal>UNION</literal>) in the
-     current implementation.
-    </para>
-   </note>
-
    <tip>
     <para>
      Omit the <literal>ROW()</literal> syntax in the common case where only one
diff --git a/src/backend/utils/adt/rowtypes.c b/src/backend/utils/adt/rowtypes.c
index 674cf0a55d..5c86259929 100644
--- a/src/backend/utils/adt/rowtypes.c
+++ b/src/backend/utils/adt/rowtypes.c
@@ -19,6 +19,7 @@
 #include "access/detoast.h"
 #include "access/htup_details.h"
 #include "catalog/pg_type.h"
+#include "common/hashfn.h"
 #include "funcapi.h"
 #include "libpq/pqformat.h"
 #include "miscadmin.h"
@@ -1766,3 +1767,251 @@ btrecordimagecmp(PG_FUNCTION_ARGS)
 {
 	PG_RETURN_INT32(record_image_cmp(fcinfo));
 }
+
+
+/*
+ * Row type hash functions
+ */
+
+Datum
+record_hash(PG_FUNCTION_ARGS)
+{
+	HeapTupleHeader record = PG_GETARG_HEAPTUPLEHEADER(0);
+	uint32		result = 0;
+	Oid			tupType;
+	int32		tupTypmod;
+	TupleDesc	tupdesc;
+	HeapTupleData tuple;
+	int			ncolumns;
+	RecordCompareData *my_extra;
+	Datum	   *values;
+	bool	   *nulls;
+
+	check_stack_depth();		/* recurses for record-type columns */
+
+	/* Extract type info from tuple */
+	tupType = HeapTupleHeaderGetTypeId(record);
+	tupTypmod = HeapTupleHeaderGetTypMod(record);
+	tupdesc = lookup_rowtype_tupdesc(tupType, tupTypmod);
+	ncolumns = tupdesc->natts;
+
+	/* Build temporary HeapTuple control structure */
+	tuple.t_len = HeapTupleHeaderGetDatumLength(record);
+	ItemPointerSetInvalid(&(tuple.t_self));
+	tuple.t_tableOid = InvalidOid;
+	tuple.t_data = record;
+
+	/*
+	 * We arrange to look up the needed hashing info just once per series
+	 * of calls, assuming the record type doesn't change underneath us.
+	 */
+	my_extra = (RecordCompareData *) fcinfo->flinfo->fn_extra;
+	if (my_extra == NULL ||
+		my_extra->ncolumns < ncolumns)
+	{
+		fcinfo->flinfo->fn_extra =
+			MemoryContextAlloc(fcinfo->flinfo->fn_mcxt,
+							   offsetof(RecordCompareData, columns) +
+							   ncolumns * sizeof(ColumnCompareData));
+		my_extra = (RecordCompareData *) fcinfo->flinfo->fn_extra;
+		my_extra->ncolumns = ncolumns;
+		my_extra->record1_type = InvalidOid;
+		my_extra->record1_typmod = 0;
+	}
+
+	if (my_extra->record1_type != tupType ||
+		my_extra->record1_typmod != tupTypmod)
+	{
+		MemSet(my_extra->columns, 0, ncolumns * sizeof(ColumnCompareData));
+		my_extra->record1_type = tupType;
+		my_extra->record1_typmod = tupTypmod;
+	}
+
+	/* Break down the tuple into fields */
+	values = (Datum *) palloc(ncolumns * sizeof(Datum));
+	nulls = (bool *) palloc(ncolumns * sizeof(bool));
+	heap_deform_tuple(&tuple, tupdesc, values, nulls);
+
+	for (int i = 0; i < ncolumns; i++)
+	{
+		Form_pg_attribute att;
+		TypeCacheEntry *typentry;
+		uint32		element_hash;
+
+		att = TupleDescAttr(tupdesc, i);
+
+		if (att->attisdropped)
+			continue;
+
+		/*
+		 * Lookup the hash function if not done already
+		 */
+		typentry = my_extra->columns[i].typentry;
+		if (typentry == NULL ||
+			typentry->type_id != att->atttypid)
+		{
+			typentry = lookup_type_cache(att->atttypid,
+										 TYPECACHE_HASH_PROC_FINFO);
+			if (!OidIsValid(typentry->hash_proc_finfo.fn_oid))
+				ereport(ERROR,
+						(errcode(ERRCODE_UNDEFINED_FUNCTION),
+						 errmsg("could not identify a hash function for type %s",
+								format_type_be(typentry->type_id))));
+			my_extra->columns[i].typentry = typentry;
+		}
+
+		/* Compute hash of element */
+		if (nulls[i])
+		{
+			element_hash = 0;
+		}
+		else
+		{
+			LOCAL_FCINFO(locfcinfo, 1);
+
+			InitFunctionCallInfoData(*locfcinfo, &typentry->hash_proc_finfo, 1,
+									 att->attcollation, NULL, NULL);
+			locfcinfo->args[0].value = values[i];
+			locfcinfo->args[0].isnull = false;
+			element_hash = DatumGetUInt32(FunctionCallInvoke(locfcinfo));
+
+			/* We don't expect hash support functions to return null */
+			Assert(!locfcinfo->isnull);
+		}
+
+		/* see hash_array() */
+		result = (result << 5) - result + element_hash;
+	}
+
+	pfree(values);
+	pfree(nulls);
+	ReleaseTupleDesc(tupdesc);
+
+	/* Avoid leaking memory when handed toasted input. */
+	PG_FREE_IF_COPY(record, 0);
+
+	PG_RETURN_UINT32(result);
+}
+
+Datum
+record_hash_extended(PG_FUNCTION_ARGS)
+{
+	HeapTupleHeader record = PG_GETARG_HEAPTUPLEHEADER(0);
+	uint64		seed = PG_GETARG_INT64(1);
+	uint64		result = 0;
+	Oid			tupType;
+	int32		tupTypmod;
+	TupleDesc	tupdesc;
+	HeapTupleData tuple;
+	int			ncolumns;
+	RecordCompareData *my_extra;
+	Datum	   *values;
+	bool	   *nulls;
+
+	check_stack_depth();		/* recurses for record-type columns */
+
+	/* Extract type info from tuple */
+	tupType = HeapTupleHeaderGetTypeId(record);
+	tupTypmod = HeapTupleHeaderGetTypMod(record);
+	tupdesc = lookup_rowtype_tupdesc(tupType, tupTypmod);
+	ncolumns = tupdesc->natts;
+
+	/* Build temporary HeapTuple control structure */
+	tuple.t_len = HeapTupleHeaderGetDatumLength(record);
+	ItemPointerSetInvalid(&(tuple.t_self));
+	tuple.t_tableOid = InvalidOid;
+	tuple.t_data = record;
+
+	/*
+	 * We arrange to look up the needed hashing info just once per series
+	 * of calls, assuming the record type doesn't change underneath us.
+	 */
+	my_extra = (RecordCompareData *) fcinfo->flinfo->fn_extra;
+	if (my_extra == NULL ||
+		my_extra->ncolumns < ncolumns)
+	{
+		fcinfo->flinfo->fn_extra =
+			MemoryContextAlloc(fcinfo->flinfo->fn_mcxt,
+							   offsetof(RecordCompareData, columns) +
+							   ncolumns * sizeof(ColumnCompareData));
+		my_extra = (RecordCompareData *) fcinfo->flinfo->fn_extra;
+		my_extra->ncolumns = ncolumns;
+		my_extra->record1_type = InvalidOid;
+		my_extra->record1_typmod = 0;
+	}
+
+	if (my_extra->record1_type != tupType ||
+		my_extra->record1_typmod != tupTypmod)
+	{
+		MemSet(my_extra->columns, 0, ncolumns * sizeof(ColumnCompareData));
+		my_extra->record1_type = tupType;
+		my_extra->record1_typmod = tupTypmod;
+	}
+
+	/* Break down the tuple into fields */
+	values = (Datum *) palloc(ncolumns * sizeof(Datum));
+	nulls = (bool *) palloc(ncolumns * sizeof(bool));
+	heap_deform_tuple(&tuple, tupdesc, values, nulls);
+
+	for (int i = 0; i < ncolumns; i++)
+	{
+		Form_pg_attribute att;
+		TypeCacheEntry *typentry;
+		uint64		element_hash;
+
+		att = TupleDescAttr(tupdesc, i);
+
+		if (att->attisdropped)
+			continue;
+
+		/*
+		 * Lookup the hash function if not done already
+		 */
+		typentry = my_extra->columns[i].typentry;
+		if (typentry == NULL ||
+			typentry->type_id != att->atttypid)
+		{
+			typentry = lookup_type_cache(att->atttypid,
+										 TYPECACHE_HASH_EXTENDED_PROC_FINFO);
+			if (!OidIsValid(typentry->hash_extended_proc_finfo.fn_oid))
+				ereport(ERROR,
+						(errcode(ERRCODE_UNDEFINED_FUNCTION),
+						 errmsg("could not identify a hash function for type %s",
+								format_type_be(typentry->type_id))));
+			my_extra->columns[i].typentry = typentry;
+		}
+
+		/* Compute hash of element */
+		if (nulls[i])
+		{
+			element_hash = 0;
+		}
+		else
+		{
+			LOCAL_FCINFO(locfcinfo, 2);
+
+			InitFunctionCallInfoData(*locfcinfo, &typentry->hash_extended_proc_finfo, 2,
+									 att->attcollation, NULL, NULL);
+			locfcinfo->args[0].value = values[i];
+			locfcinfo->args[0].isnull = false;
+			locfcinfo->args[1].value = Int64GetDatum(seed);
+			locfcinfo->args[0].isnull = false;
+			element_hash = DatumGetUInt64(FunctionCallInvoke(locfcinfo));
+
+			/* We don't expect hash support functions to return null */
+			Assert(!locfcinfo->isnull);
+		}
+
+		/* see hash_array_extended() */
+		result = (result << 5) - result + element_hash;
+	}
+
+	pfree(values);
+	pfree(nulls);
+	ReleaseTupleDesc(tupdesc);
+
+	/* Avoid leaking memory when handed toasted input. */
+	PG_FREE_IF_COPY(record, 0);
+
+	PG_RETURN_UINT64(result);
+}
diff --git a/src/include/catalog/pg_amop.dat b/src/include/catalog/pg_amop.dat
index 1dfb6fd373..dccbeabcf4 100644
--- a/src/include/catalog/pg_amop.dat
+++ b/src/include/catalog/pg_amop.dat
@@ -979,6 +979,11 @@
   amoprighttype => 'oidvector', amopstrategy => '1',
   amopopr => '=(oidvector,oidvector)', amopmethod => 'hash' },
 
+# record_ops
+{ amopfamily => 'hash/record_ops', amoplefttype => 'record',
+  amoprighttype => 'record', amopstrategy => '1',
+  amopopr => '=(record,record)', amopmethod => 'hash' },
+
 # text_ops
 { amopfamily => 'hash/text_ops', amoplefttype => 'text',
   amoprighttype => 'text', amopstrategy => '1', amopopr => '=(text,text)',
diff --git a/src/include/catalog/pg_amproc.dat b/src/include/catalog/pg_amproc.dat
index a8e0c4ff8a..e000421788 100644
--- a/src/include/catalog/pg_amproc.dat
+++ b/src/include/catalog/pg_amproc.dat
@@ -433,6 +433,10 @@
   amprocrighttype => 'uuid', amprocnum => '1', amproc => 'uuid_hash' },
 { amprocfamily => 'hash/uuid_ops', amproclefttype => 'uuid',
   amprocrighttype => 'uuid', amprocnum => '2', amproc => 'uuid_hash_extended' },
+{ amprocfamily => 'hash/record_ops', amproclefttype => 'record',
+  amprocrighttype => 'record', amprocnum => '1', amproc => 'record_hash' },
+{ amprocfamily => 'hash/record_ops', amproclefttype => 'record',
+  amprocrighttype => 'record', amprocnum => '2', amproc => 'record_hash_extended' },
 { amprocfamily => 'hash/pg_lsn_ops', amproclefttype => 'pg_lsn',
   amprocrighttype => 'pg_lsn', amprocnum => '1', amproc => 'pg_lsn_hash' },
 { amprocfamily => 'hash/pg_lsn_ops', amproclefttype => 'pg_lsn',
diff --git a/src/include/catalog/pg_opclass.dat b/src/include/catalog/pg_opclass.dat
index f2342bb328..be5712692f 100644
--- a/src/include/catalog/pg_opclass.dat
+++ b/src/include/catalog/pg_opclass.dat
@@ -114,6 +114,8 @@
   opcfamily => 'hash/oidvector_ops', opcintype => 'oidvector' },
 { opcmethod => 'btree', opcname => 'record_ops',
   opcfamily => 'btree/record_ops', opcintype => 'record' },
+{ opcmethod => 'hash', opcname => 'record_ops',
+  opcfamily => 'hash/record_ops', opcintype => 'record' },
 { opcmethod => 'btree', opcname => 'record_image_ops',
   opcfamily => 'btree/record_image_ops', opcintype => 'record',
   opcdefault => 'f' },
diff --git a/src/include/catalog/pg_operator.dat b/src/include/catalog/pg_operator.dat
index 7cc812adda..1ffd826679 100644
--- a/src/include/catalog/pg_operator.dat
+++ b/src/include/catalog/pg_operator.dat
@@ -3064,7 +3064,7 @@
 
 # generic record comparison operators
 { oid => '2988', oid_symbol => 'RECORD_EQ_OP', descr => 'equal',
-  oprname => '=', oprcanmerge => 't', oprleft => 'record', oprright => 'record',
+  oprname => '=', oprcanmerge => 't', oprcanhash => 't', oprleft => 'record', oprright => 'record',
   oprresult => 'bool', oprcom => '=(record,record)',
   oprnegate => '<>(record,record)', oprcode => 'record_eq', oprrest => 'eqsel',
   oprjoin => 'eqjoinsel' },
diff --git a/src/include/catalog/pg_opfamily.dat b/src/include/catalog/pg_opfamily.dat
index cf0fb325b3..11c7ad2c14 100644
--- a/src/include/catalog/pg_opfamily.dat
+++ b/src/include/catalog/pg_opfamily.dat
@@ -76,6 +76,8 @@
   opfmethod => 'hash', opfname => 'oidvector_ops' },
 { oid => '2994',
   opfmethod => 'btree', opfname => 'record_ops' },
+{ oid => '9611',
+  opfmethod => 'hash', opfname => 'record_ops' },
 { oid => '3194',
   opfmethod => 'btree', opfname => 'record_image_ops' },
 { oid => '1994', oid_symbol => 'TEXT_BTREE_FAM_OID',
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 22340baf1c..1d113272fd 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -9670,6 +9670,13 @@
   proname => 'btrecordcmp', prorettype => 'int4',
   proargtypes => 'record record', prosrc => 'btrecordcmp' },
 
+{ oid => '9609', descr => 'hash',
+  proname => 'record_hash', prorettype => 'int4', proargtypes => 'record',
+  prosrc => 'record_hash' },
+{ oid => '9610', descr => 'hash',
+  proname => 'record_hash_extended', prorettype => 'int8', proargtypes => 'record int8',
+  prosrc => 'record_hash_extended' },
+
 # record comparison using raw byte images
 { oid => '3181',
   proname => 'record_image_eq', prorettype => 'bool',
diff --git a/src/test/regress/expected/hash_func.out b/src/test/regress/expected/hash_func.out
index e6e3410aaa..9c11e16b0b 100644
--- a/src/test/regress/expected/hash_func.out
+++ b/src/test/regress/expected/hash_func.out
@@ -298,3 +298,15 @@ WHERE  hash_range(v)::bit(32) != hash_range_extended(v, 0)::bit(32)
 -------+----------+-----------+-----------
 (0 rows)
 
+CREATE TYPE t1 AS (a int, b text);
+SELECT v as value, record_hash(v)::bit(32) as standard,
+       record_hash_extended(v, 0)::bit(32) as extended0,
+       record_hash_extended(v, 1)::bit(32) as extended1
+FROM   (VALUES (row(1, 'aaa')::t1, row(2, 'bbb'), row(-1, 'ccc'))) x(v)
+WHERE  record_hash(v)::bit(32) != record_hash_extended(v, 0)::bit(32)
+       OR record_hash(v)::bit(32) = record_hash_extended(v, 1)::bit(32);
+ value | standard | extended0 | extended1 
+-------+----------+-----------+-----------
+(0 rows)
+
+DROP TYPE t1;
diff --git a/src/test/regress/expected/join.out b/src/test/regress/expected/join.out
index a46b1573bd..4a375deff3 100644
--- a/src/test/regress/expected/join.out
+++ b/src/test/regress/expected/join.out
@@ -2707,6 +2707,7 @@ select a.idv, b.idv from tidv a, tidv b where a.idv = b.idv;
 (5 rows)
 
 set enable_mergejoin = 0;
+set enable_hashjoin = 0;
 explain (costs off)
 select a.idv, b.idv from tidv a, tidv b where a.idv = b.idv;
                      QUERY PLAN                     
diff --git a/src/test/regress/expected/with.out b/src/test/regress/expected/with.out
index 457f3bf04f..6a01ddfdd6 100644
--- a/src/test/regress/expected/with.out
+++ b/src/test/regress/expected/with.out
@@ -616,6 +616,44 @@ select * from search_graph;
  2 | 3 | arc 2 -> 3 | f        | {"(1,4)","(4,5)","(5,1)","(1,2)","(2,3)"}
 (25 rows)
 
+-- again with union distinct to test row-type hash support
+with recursive search_graph(f, t, label, is_cycle, path) as (
+	select *, false, array[row(g.f, g.t)] from graph g
+	union distinct
+	select g.*, row(g.f, g.t) = any(path), path || row(g.f, g.t)
+	from graph g, search_graph sg
+	where g.f = sg.t and not is_cycle
+)
+select * from search_graph;
+ f | t |   label    | is_cycle |                   path                    
+---+---+------------+----------+-------------------------------------------
+ 1 | 2 | arc 1 -> 2 | f        | {"(1,2)"}
+ 1 | 3 | arc 1 -> 3 | f        | {"(1,3)"}
+ 2 | 3 | arc 2 -> 3 | f        | {"(2,3)"}
+ 1 | 4 | arc 1 -> 4 | f        | {"(1,4)"}
+ 4 | 5 | arc 4 -> 5 | f        | {"(4,5)"}
+ 5 | 1 | arc 5 -> 1 | f        | {"(5,1)"}
+ 1 | 2 | arc 1 -> 2 | f        | {"(5,1)","(1,2)"}
+ 1 | 3 | arc 1 -> 3 | f        | {"(5,1)","(1,3)"}
+ 1 | 4 | arc 1 -> 4 | f        | {"(5,1)","(1,4)"}
+ 2 | 3 | arc 2 -> 3 | f        | {"(1,2)","(2,3)"}
+ 4 | 5 | arc 4 -> 5 | f        | {"(1,4)","(4,5)"}
+ 5 | 1 | arc 5 -> 1 | f        | {"(4,5)","(5,1)"}
+ 1 | 2 | arc 1 -> 2 | f        | {"(4,5)","(5,1)","(1,2)"}
+ 1 | 3 | arc 1 -> 3 | f        | {"(4,5)","(5,1)","(1,3)"}
+ 1 | 4 | arc 1 -> 4 | f        | {"(4,5)","(5,1)","(1,4)"}
+ 2 | 3 | arc 2 -> 3 | f        | {"(5,1)","(1,2)","(2,3)"}
+ 4 | 5 | arc 4 -> 5 | f        | {"(5,1)","(1,4)","(4,5)"}
+ 5 | 1 | arc 5 -> 1 | f        | {"(1,4)","(4,5)","(5,1)"}
+ 1 | 2 | arc 1 -> 2 | f        | {"(1,4)","(4,5)","(5,1)","(1,2)"}
+ 1 | 3 | arc 1 -> 3 | f        | {"(1,4)","(4,5)","(5,1)","(1,3)"}
+ 1 | 4 | arc 1 -> 4 | t        | {"(1,4)","(4,5)","(5,1)","(1,4)"}
+ 2 | 3 | arc 2 -> 3 | f        | {"(4,5)","(5,1)","(1,2)","(2,3)"}
+ 4 | 5 | arc 4 -> 5 | t        | {"(4,5)","(5,1)","(1,4)","(4,5)"}
+ 5 | 1 | arc 5 -> 1 | t        | {"(5,1)","(1,4)","(4,5)","(5,1)"}
+ 2 | 3 | arc 2 -> 3 | f        | {"(1,4)","(4,5)","(5,1)","(1,2)","(2,3)"}
+(25 rows)
+
 -- ordering by the path column has same effect as SEARCH DEPTH FIRST
 with recursive search_graph(f, t, label, is_cycle, path) as (
 	select *, false, array[row(g.f, g.t)] from graph g
diff --git a/src/test/regress/sql/hash_func.sql b/src/test/regress/sql/hash_func.sql
index a3e2decc2c..747c79b915 100644
--- a/src/test/regress/sql/hash_func.sql
+++ b/src/test/regress/sql/hash_func.sql
@@ -220,3 +220,12 @@ CREATE TYPE mood AS ENUM ('sad', 'ok', 'happy');
         (int4range(550274, 1550274)), (int4range(1550275, 208112489))) x(v)
 WHERE  hash_range(v)::bit(32) != hash_range_extended(v, 0)::bit(32)
        OR hash_range(v)::bit(32) = hash_range_extended(v, 1)::bit(32);
+
+CREATE TYPE t1 AS (a int, b text);
+SELECT v as value, record_hash(v)::bit(32) as standard,
+       record_hash_extended(v, 0)::bit(32) as extended0,
+       record_hash_extended(v, 1)::bit(32) as extended1
+FROM   (VALUES (row(1, 'aaa')::t1, row(2, 'bbb'), row(-1, 'ccc'))) x(v)
+WHERE  record_hash(v)::bit(32) != record_hash_extended(v, 0)::bit(32)
+       OR record_hash(v)::bit(32) = record_hash_extended(v, 1)::bit(32);
+DROP TYPE t1;
diff --git a/src/test/regress/sql/join.sql b/src/test/regress/sql/join.sql
index 1403e0ffe7..023290bd52 100644
--- a/src/test/regress/sql/join.sql
+++ b/src/test/regress/sql/join.sql
@@ -700,6 +700,7 @@ CREATE TEMP TABLE tt2 ( tt2_id int4, joincol int4 );
 select a.idv, b.idv from tidv a, tidv b where a.idv = b.idv;
 
 set enable_mergejoin = 0;
+set enable_hashjoin = 0;
 
 explain (costs off)
 select a.idv, b.idv from tidv a, tidv b where a.idv = b.idv;
diff --git a/src/test/regress/sql/with.sql b/src/test/regress/sql/with.sql
index 2eea297a71..7aa164b997 100644
--- a/src/test/regress/sql/with.sql
+++ b/src/test/regress/sql/with.sql
@@ -317,6 +317,16 @@ CREATE TEMPORARY TABLE tree(
 )
 select * from search_graph;
 
+-- again with union distinct to test row-type hash support
+with recursive search_graph(f, t, label, is_cycle, path) as (
+	select *, false, array[row(g.f, g.t)] from graph g
+	union distinct
+	select g.*, row(g.f, g.t) = any(path), path || row(g.f, g.t)
+	from graph g, search_graph sg
+	where g.f = sg.t and not is_cycle
+)
+select * from search_graph;
+
 -- ordering by the path column has same effect as SEARCH DEPTH FIRST
 with recursive search_graph(f, t, label, is_cycle, path) as (
 	select *, false, array[row(g.f, g.t)] from graph g
-- 
2.28.0