On Wed, Mar 30, 2005 at 02:46:37PM -0800, Kemin Zhou wrote: > I just found out one strange behavior of the SQL engine. This may be fixed. > > table 1 > create table table1 ( id integer, something text); > > create table table2 (id integer, otherthing text); > > select * > from table1 t1, table2 t2 > where t1.id=table2.id; > > -- here I made a mistake in the where clause I should have used > -- where t1.id=t2.id > > This query produces a lot of MORE rows than it should be, and it is > doing cross join.
In 7.4 and later you'll get an error if you disable add_missing_from: SET add_missing_from TO off; SELECT * FROM table1 t1, table2 t2 WHERE t1.id = table2.id; ERROR: missing FROM-clause entry for table "table2" See the "Run-time Configuration" section of the "Server Run-time Environment" chapter in the documentation for more info. http://www.postgresql.org/docs/8.0/interactive/runtime-config.html#GUC-ADD-MISSING-FROM There's been a proposal to disable add_missing_from by default in a future version of PostgreSQL. -- Michael Fuhr http://www.fuhr.org/~mfuhr/ ---------------------------(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
