DBLINK_GET_PKEY(3)					  PostgreSQL 9.2.7 Documentation					DBLINK_GET_PKEY(3)

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
	   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 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)

PostgreSQL 9.2.7						    2014-02-17							DBLINK_GET_PKEY(3)