Tom Lane wrote:
Hardly surprising --- a search on the index's lowest-order column would
require scanning practically all of the index. (If you think about the
ordering of the index entries you'll see why.) If this is a typical
query then you need a separate index on transaction_time_commit.
Yes, actually I just moved transaction_time_commit column to the
begining of the index, since, most of the time I run queries based on
transaction_time_commit and then transaction_client_id and
transaction_destination_id.
The fine manual goes into some detail about how to design indexes;
http://www.postgresql.org/docs/8.3/static/indexes.html
particularly 11.3, 11.5.
I see it now. I read the manual concerning CREATE INDEX command, and
there is no mention of multicolumn indices, did not notice Note that
points to Chapter 11.
Mike
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