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


    dblink_get_pkey(text relname) returns setof dblink_pkey_results


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



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

Return Value

Returns one row for each primary key field, or no rows if the relation has no primary key. The result rowtype is defined as

CREATE TYPE dblink_pkey_results AS (position int, colname text);


test=# create table foobar(f1 int, f2 int, f3 int,
test(#   primary key(f1,f2,f3));
test=# select * from dblink_get_pkey('foobar');
 position | colname
        1 | f1
        2 | f2
        3 | f3
(3 rows)