1DBLINK_GET_PKEY(3) PostgreSQL 9.2.24 Documentation DBLINK_GET_PKEY(3)
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6 dblink_get_pkey - returns the positions and field names of a relation's
7 primary key fields
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10 dblink_get_pkey(text relname) returns setof dblink_pkey_results
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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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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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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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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 9.2.24 2017-11-06 DBLINK_GET_PKEY(3)