On Wed, 2002-05-29 at 02:36, Joel Burton wrote: > > -----Original Message----- > joel@joel=# select true and seeme(); > NOTICE: seeme > ?column? > ---------- > t > (1 row) > > > It certainly appears to be short circuiting for "select false and seeme()", > for instance. > > It appears that this isn't short-circuiting by order of expressions, however > (as Perl and other languages do); for example, "select seeme() or true" > doesn't ever get to seeme(). I assume PG can simply see that the statement > "true" will evaluate to true (clever, that PG!), and therefore it doesn't > have to evaluate seeme() ?
Are these intricacies of SQL standardised anywhere ? I know that gcc and other ccs can achieve different results depending on optimisation level - usually this is considered a bug. But as PG runs always (?) at the maximum optimisation, should there be such guarantees ? Or is it something that should be ind doc's/faq's (- don't rely on side effects) ? ------------------------ Hannu ---------------------------(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
