Re: join table with empty fields and default - Mailing list pgsql-general

On Sat, Jul 22, 2006 at 12:47:42PM -0700, quickcur@yahoo.com wrote:
> I would like to join table user and userwork, where if a user has a
> work, I list it. If he does not, I give it some default value "no work"

You could use an outer join and COALESCE.

http://www.postgresql.org/docs/8.1/interactive/tutorial-join.html
http://www.postgresql.org/docs/8.1/interactive/queries-table-expressions.html#QUERIES-JOIN
http://www.postgresql.org/docs/8.1/interactive/functions-conditional.html#AEN12639

Example:

SELECT u.id, u.name, u.address, COALESCE(uw.work, 'no work') AS work
FROM "user" AS u
LEFT OUTER JOIN userwork AS uw ON uw.userid = u.id;

--
Michael Fuhr