Tom, Juan, Wouldn't this simple SQL do the trick?
CREATE OR REPLACE FUNCTION pk_column(text) RETURNS SETOF text AS ' SELECT attname::text FROM pg_class, pg_constraint, pg_attribute WHERE pg_class.oid = conrelid AND contype=''p'' AND attrelid = pg_class.oid AND attnum = ANY (conkey) AND relname=$1; ' LANGUAGE sql VOLATILE STRICT; > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Tom Lane > Sent: Tuesday, May 17, 2005 4:49 AM > To: Juan Pablo Espino > Cc: pgsql-hackers@postgresql.org > Subject: Re: [HACKERS] Returning the name of a primary key > > Juan Pablo Espino <[EMAIL PROTECTED]> writes: > > I need to write a function that retrieve the name of at least one > > table primary key, if it exists. The only argument passed to the > > function is the table name. I have thought something like this: > > You need to be searching the list of indexes, not the > attributes per se. > ATExecDropNotNull() might be a useful example. > > regards, tom lane > > ---------------------------(end of > broadcast)--------------------------- > TIP 9: the planner will ignore your desire to choose an index > scan if your > joining column's datatypes do not match > > ---------------------------(end of broadcast)--------------------------- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq