What is the status of this feature addition? ---------------------------------------------------------------------------
Stephen Frost wrote: -- Start of PGP signed section. > * Tom Lane ([EMAIL PROTECTED]) wrote: > > (However, now that we support nulls in arrays, meseems a more consistent > > definition would be that it allows null inputs and just includes them in > > the output. So probably you do need it non-strict.) > > This was my intention. > > > I'm inclined to think that this example demonstrates a deficiency in the > > aggregate-function design: there should be a way to declare what we're > > really doing. But I don't know exactly what that should look like. > > I agree and would much rather have a clean solution which works with the > design than one which has to work outside it. When I first was trying > to decide on the state-type I was looking through the PG catalogs for > essentially a "complex C type" which translated to a void*. Perhaps > such a type could be added. Unless that's considered along the lines of > an 'any' type it'd cause problems for the polymorphism aspect. > > Another alternative would be to provide a seperate area for each > aggregate to put any other information it needs. This would almost > certainly only be available to C functions but would essentially be a > void* which is provided through the AggState structure but tracked by > the aggregator routines and reset for each aggregate function being > run. If that's acceptable, I don't think it'd be all that difficult to > implement. With that, aaccum_sfunc and aaccum_ffunc would ignore the > state variable passed to them in favor of their custom structure > available through fcinfo->AggState (I expect they'd just keep the > state variable NULL and be marked non-strict, or set it to some constant > if necessary). The pointer would have to be tracked somewhere and then > copied in/out on each call, but that doesn't seem too difficult to me. > After all, the state variable is already being tracked somewhere, this > would just sit next to it, in my head anyway. > > I've got some time this weekend and would be happy to take a shot at > the second proposal if that's generally acceptable. > > Thanks, > > Stephen -- End of PGP section, PGP failed! -- Bruce Momjian <[EMAIL PROTECTED]> http://momjian.us EnterpriseDB http://www.enterprisedb.com + If your life is a hard drive, Christ can be your backup. + ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster
