On Thu, Jun 4, 2009 at 1:23 PM, Brandon Metcalf <brandon@xxxxxxxxxxxxxxxxxx> wrote: > Got it. Currently, it doesn't have a column for an ID, but I can add > one if this is the only way. Actually any column with a unique index on it will work. It doesn't have to be primary key or even a serial id. ANSI-SQL 92 allows for the following syntax: CONSTRAINT Only_one_row CHECK( 1 >= (SELECT COUNT(*) FROM _this_table;)); However, I have yet to find a RDBMS (PostgreSQL included) that supports select statements in a table's check constraint. -- Regards, Richard Broersma Jr. Visit the Los Angeles PostgreSQL Users Group (LAPUG) http://pugs.postgresql.org/lapug -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
