On Tue, Jul 27, 2010 at 7:16 PM, Tom Lane <t...@sss.pgh.pa.us> wrote: > Daniel Grace <dgr...@wingsnw.com> writes: >> But if we SELECT >> SOME_INTEGER_AGGREGATE(DISTINCT floatcol ORDER BY floatcol), should >> the DISTINCT operate on floatcol (i.e. 1.1 and 1.2 are distinct, even >> if it means the function is called with '1' twice) or >> floatcol::integer (1.1 and 1.2 are not distinct)? > > Yes. The current implementation has the advantage that any > unique-ifying step is guaranteed to produce outputs that are distinct > from the point of view of the aggregate function, whereas if we try to > keep the two operations at arms-length, then either we lose that > property or we sort-and-unique twice :-(.
Am I misreading this, or did you just answer an "either-or" question with "yes"? -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise Postgres Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
