Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Hm, that means there's only one grouping column (and it's the second
> tlist entry of the child plan node). So that seems conclusive that
> the unique-ification is being done wrong.
Further confirmation using the EXPLAIN patch with Antonin's v2
patch against the table before any EXPLAIN or ANALYZE:
Hash Join (cost=37.12..80.40 rows=442 width=12)
Hash Cond: (((upper.f2)::double precision = lower.f3) AND (upper.f1 = lower.f2))
-> Seq Scan on subselect_tbl upper (cost=0.00..27.70 rows=1770 width=16)
-> Hash (cost=34.12..34.12 rows=200 width=12)
-> HashAggregate (cost=32.12..34.12 rows=200 width=12)
Group Key: lower.f2
-> Seq Scan on subselect_tbl lower (cost=0.00..27.70 rows=1770 width=12)
The additional information is so useful, I'm all for committing
that patch.
--
Kevin Grittner
EDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company