The following bug has been logged on the website:
Bug reference: 6719
Logged by: BLove
Email address: blove319@hotmail.com
PostgreSQL version: 9.1.3
Operating system: Centos 5
Description:=20=20=20=20=20=20=20=20
After doing an equality search on an indexed field, PG is doing a filter on
the same value using a regex. That appears to be a useless operation that
will only consume cpu cycles.
explain select * from transactions.subscriber_504700_txns_y2012m05 lh where
lh.account_code LIKE '34016975\_DAT\_FR\_HF';
QUERY PLAN
=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=
=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=
=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20
---------------------------------------------------------------------------=
-------------------------------------------------------------------
Index Scan using idx_subscriber_504700_txns_y2012m05_account_code on
subscriber_504700_txns_y2012m05 lh (cost=3D0.00..17.02 rows=3D3 width=3D13=
1)
Index Cond: (account_code =3D '34016975_DAT_FR_HF'::text)
Filter: (account_code ~~ '34016975\_DAT\_FR\_HF'::text)