Florian Pflug <f...@phlo.org> writes: > On Jan10, 2014, at 19:08 , Tom Lane <t...@sss.pgh.pa.us> wrote: >> Although, having said that ... maybe "build your own aggregate" would >> be a reasonable suggestion for people who need this? I grant that >> it's going to be a minority requirement, maybe even a small minority >> requirement. People who have the chops to get this sort of thing right >> can probably manage a custom aggregate definition.
> So we'd put a footgun into the hands of people who don't know what they're > doing, to be fired for performance's sake, and leave it to the people > who know what they are doing to put the safety on? If I may put words in Kevin's mouth, I think his point is that having float8 sum() at all is a foot-gun, and that's hard to deny. You need to know how to use it safely. A compromise compromise might be to provide these alternative "safer" aggregates built-in. Or, depending on what color you like your bikeshed, leave the standard aggregates alone and define "fast_sum" etc for the less safe versions. In any case it'd be incumbent on us to document the tradeoffs. regards, tom lane -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers