Hi.
For an INNER JOINed query, EXPLAIN says that a "nested loop" is responsible
for the big part of the time needed to run.
The 2 tables JOINed are:
T1: multi-million rows
T2: few dozens rows
The join is though a single column in both sides and it's NOT a PK in either
table. But I have indexes in both T1 and T2 for that column.
I've read in the "Explaining EXPLAIN" by Rober Treat
(at http://wiki.postgresql.org/wiki/Image:OSCON2005-ExplainingExplain.sxi)
that this nested loop can be slow because of lacking of indexes.
Is there any hint to try to speed that query up?
As of now, only a REINDEX can help thanks to caching, I presume.
But the EXPLAIN still says there's a slow nested loop.
--
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