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* Re: Get info about the index
@ 2025-08-02 00:06 Igor Korot <[email protected]>
0 siblings, 1 reply; 2+ messages in thread
From: Igor Korot @ 2025-08-02 00:06 UTC (permalink / raw)
To: Laurenz Albe <[email protected]>; +Cc: David Barbour <[email protected]>; Jon Zeppieri <[email protected]>; Christophe Pettus <[email protected]>; Adrian Klaver <[email protected]>; pgsql-generallists.postgresql.org <[email protected]>
Hi, Laurenz,
On Tue, Jul 29, 2025 at 7:07 AM Laurenz Albe <[email protected]> wrote:
>
> On Tue, 2025-07-29 at 06:46 -0500, Igor Korot wrote:
> > SELECT
> > t.relname AS table_name,
> > i.relname AS index_name,
> > a.attname AS column_name
> > FROM
> > pg_class t,
> > pg_class i,
> > pg_index ix,
> > pg_attribute a
> > WHERE
> > t.oid = ix.indrelid AND
> > i.oid = ix.indexrelid AND
> > a.attrelid = t.oid AND
> > a.attnum = ANY(ix.indkey) AND
> > t.relkind = 'r' AND -- 'r' for regular table
> > t.relname = 'your_table_name' -- Optional: filter by table name
> > ORDER BY
> > t.relname,
> > i.relname,
> > a.attnum;
> >
> > I can build on top of this query, however I have 2 issues:
> >
> > First and most important one - they are filtering by just table name.
> > How can I filter by the fully qualified name - catalog.schema.table?
>
> "catalog" is irrelevant, since PostgreSQL doesn't allow cross-database queries.
>
> To add a filter for the schema, use
>
> AND t.relnamespace = 'schemaname'::regnamespace
>
> > Second - how cn I get the partial index condition? Either the whole
> > WHERE clause (which I will have to parse)
> > or the broken down one (field, condition {AND|OR} field, condition}?
>
> SELECT pg_get_expr(ix.indpred, t.oid)
I'm looking at the pg_index table and I see it has:
[quote]
indisexclusion bool
If true, this index supports an exclusion constraint
[/quote]
If I read the docs correctly, this field indicates whether the
WHERE condition is actually present.
Am I right?
Thank you.
>
> Yours,
> Laurenz Albe
^ permalink raw reply [nested|flat] 2+ messages in thread
* Re: Get info about the index
@ 2025-08-02 00:13 Adrian Klaver <[email protected]>
parent: Igor Korot <[email protected]>
0 siblings, 0 replies; 2+ messages in thread
From: Adrian Klaver @ 2025-08-02 00:13 UTC (permalink / raw)
To: Igor Korot <[email protected]>; Laurenz Albe <[email protected]>; +Cc: David Barbour <[email protected]>; Jon Zeppieri <[email protected]>; Christophe Pettus <[email protected]>; pgsql-generallists.postgresql.org <[email protected]>
On 8/1/25 17:06, Igor Korot wrote:
> Hi, Laurenz,
>
> I'm looking at the pg_index table and I see it has:
>
> [quote]
> indisexclusion bool
>
> If true, this index supports an exclusion constraint
> [/quote]
>
> If I read the docs correctly, this field indicates whether the
> WHERE condition is actually present.
>
> Am I right?
No, it refers to:
https://www.postgresql.org/docs/current/ddl-constraints.html#DDL-CONSTRAINTS-EXCLUSION
>
> Thank you.
>
>>
>> Yours,
>> Laurenz Albe
--
Adrian Klaver
[email protected]
^ permalink raw reply [nested|flat] 2+ messages in thread
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2025-08-02 00:06 Re: Get info about the index Igor Korot <[email protected]>
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