On 08/02/11 11:05, Jorge Arévalo wrote:
2011/2/8 Stefan Keller<sfkel...@gmail.com>:
" Hash Cond: (TABLE_C.STR_FIELD = TABLE_B.STR_FIELD)"
tells me that these two longish strings are compared first.
Did you already try to index TABLE_C.STR_FIELD and TABLE_B.STR_FIELD
as hash instead btree?
I thought hash indexes were discouraged over btree. Anyway, I'll test it.
Absolutely. You do not want to be using Hash Indexes these days - stick
with B-Tree. The hash refers to the method by which the executor matches
the two column fields and is not related to the underlying index type.
ATB,
Mark.
--
Mark Cave-Ayland - Senior Technical Architect
PostgreSQL - PostGIS
Sirius Corporation plc - control through freedom
http://www.siriusit.co.uk
t: +44 870 608 0063
Sirius Labs: http://www.siriusit.co.uk/labs
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