NAME¶

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

SYNOPSIS¶

dblink_get_pkey(text relname) returns setof dblink_pkey_results

DESCRIPTION¶

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.

ARGUMENTS¶

relname

RETURN VALUE¶

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

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

The position column simply runs from 1 to N; it is the number of the field within the primary key, not the number within the table's columns.

EXAMPLES¶

CREATE TABLE foobar (


    f1 int,


    f2 int,


    f3 int,


    PRIMARY KEY (f1, f2, f3)
);
CREATE TABLE
SELECT * FROM dblink_get_pkey('foobar');


 position | colname
----------+---------


        1 | f1


        2 | f2


        3 | f3
(3 rows)