2007/10/12, Clemens Schwaighofer <[EMAIL PROTECTED]>: > hi, > > thats the first time I am a bit confused by a query not working. > > I have this table: > > gullevek=# \d test > Table "public.test" > Column | Type | Modifiers > ---------+-------------------+-------------------------------------------------------- > test_id | integer | not null default > nextval('test_test_id_seq'::regclass) > email_a | character varying | > email_b | character varying | > Indexes: > "test_pkey" PRIMARY KEY, btree (test_id) > > with this content: > > gullevek=# select * from test; > test_id | email_a | email_b > ---------+---------------+------------- > 2 | [EMAIL PROTECTED] | [EMAIL PROTECTED] > 1 | [EMAIL PROTECTED] | > (2 rows) > > if I do this select: > > select * from (select test_id, email_a FROM test WHERE email_a = > '[EMAIL PROTECTED]') as s, (select test_id, email_b from test where email_b = > '[EMAIL PROTECTED]') as t; >
you get 0 rows. [EMAIL PROTECTED] isn't anywhere and [EMAIL PROTECTED] cannot do pair with any. else 0 * 1 = 0 Pavel ---------------------------(end of broadcast)--------------------------- TIP 1: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly