Re: [PATCHES] Proof of concept for MIN/MAX optimization
Tom Lane wrote: Mark Kirkwood <[EMAIL PROTECTED]> writes: The handling of nulls is a little unexpected (still todo?) : Yeah, that was broken in the first draft :-( ... I think it's OK in the committed version though. (post cvs update) yeah - looks good! regards Mark ---(end of broadcast)--- TIP 7: don't forget to increase your free space map settings
Re: [PATCHES] Proof of concept for MIN/MAX optimization
Mark Kirkwood <[EMAIL PROTECTED]> writes: > The handling of nulls is a little unexpected (still todo?) : Yeah, that was broken in the first draft :-( ... I think it's OK in the committed version though. regards, tom lane ---(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
Re: [PATCHES] Proof of concept for MIN/MAX optimization
Tom Lane wrote: I haven't done the work yet to add a column to pg_aggregate, so this just knows about optimizing a couple of hard-wired cases (int4 and text). Other than that it's reasonably complete, I think. Comments? Looks good : regression=# explain select max(unique1) from tenk1; QUERY PLAN - Result (cost=0.15..0.16 rows=1 width=0) InitPlan -> Limit (cost=0.00..0.15 rows=1 width=4) -> Index Scan Backward using tenk1_unique1 on tenk1 (cost=0.00..1512.59 rows=1 width=4) (4 rows) The handling of nulls is a little unexpected (still todo?) : regression=# insert into tenk2 (unique1,unique2) values(null, 1); INSERT 0 1 regression=# select max(unique1) from tenk2; max - (1 row) regression=# set enable_indexscan=0; SET regression=# select max(unique1) from tenk2; max -- (1 row) cheers Mark ---(end of broadcast)--- TIP 1: subscribe and unsubscribe commands go to [EMAIL PROTECTED]