PostgreSQL version: 7.4.3 (RPMs from ftp.au.postgresql.org) Operating Sysem: Fedora Core 1
CREATE TABLE t1 (i INTEGER, j INTEGER); INSERT INTO t1 VALUES (1, NULL); CREATE TABLE t2 AS SELECT * FROM t1; SELECT * FROM t1 JOIN t2 USING (i, j); i | j ---+--- (0 rows) I believe the one row, which is identically present in both table, should be selected. The problem occurs because of the NULL value. ---------------------------(end of broadcast)--------------------------- TIP 3: 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