1DBLINK_GET_PKEY(3)       PostgreSQL 12.6 Documentation      DBLINK_GET_PKEY(3)
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NAME

6       dblink_get_pkey - returns the positions and field names of a relation's
7       primary key fields
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SYNOPSIS

10       dblink_get_pkey(text relname) returns setof dblink_pkey_results
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DESCRIPTION

13       dblink_get_pkey provides information about the primary key of a
14       relation in the local database. This is sometimes useful in generating
15       queries to be sent to remote databases.
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ARGUMENTS

18       relname
19           Name of a local relation, for example foo or myschema.mytab.
20           Include double quotes if the name is mixed-case or contains special
21           characters, for example "FooBar"; without quotes, the string will
22           be folded to lower case.
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RETURN VALUE

25       Returns one row for each primary key field, or no rows if the relation
26       has no primary key. The result row type is defined as
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28           CREATE TYPE dblink_pkey_results AS (position int, colname text);
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30       The position column simply runs from 1 to N; it is the number of the
31       field within the primary key, not the number within the table's
32       columns.
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EXAMPLES

35           CREATE TABLE foobar (
36               f1 int,
37               f2 int,
38               f3 int,
39               PRIMARY KEY (f1, f2, f3)
40           );
41           CREATE TABLE
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43           SELECT * FROM dblink_get_pkey('foobar');
44            position | colname
45           ----------+---------
46                   1 | f1
47                   2 | f2
48                   3 | f3
49           (3 rows)
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53PostgreSQL 12.6                      2021                   DBLINK_GET_PKEY(3)