sqlite3 performance problems only in python
Piet van Oostrum
piet at cs.uu.nl
Thu Jul 23 14:20:50 EDT 2009
>>>>> Stef Mientki <stef.mientki at gmail.com> (SM) wrote:
>SM> btw, I don't know if it's of any importance, the SQL-statement I perform is
>SM> select OPNAMEN.*, NAME, NAME_, SCORES.SCORE, PATIENT.*
>SM> from OPNAMEN
>SM> inner join POID_VLID on OPNAMEN.POID = POID_VLID.POID
>SM> inner join VRAAGLST on VRAAGLST.VLID = POID_VLID.VLID
>SM> inner join VLID_SSID on VRAAGLST.VLID = VLID_SSID.VLID
>SM> inner join SUBSCHAAL_GEGEVENS on SUBSCHAAL_GEGEVENS.SSID = VLID_SSID.SSID
>SM> inner join POID_SSID_SCID on ( OPNAMEN.POID =
>SM> POID_SSID_SCID.POID ) and
>SM> ( SUBSCHAAL_GEGEVENS.SSID =
>SM> POID_SSID_SCID.SSID )
>SM> inner join SCORES on SCORES.SCID =
>SM> POID_SSID_SCID.SCID
>SM> inner join PID_POID on OPNAMEN.POID = PID_POID.POID
>SM> inner join PATIENT on PATIENT.PID = PID_POID.PID
>SM> where substr ( lower( NAME) , 1, 6) = 'cis20r'
>SM> and lower ( NAME_ ) = 'fatigue'
>SM> and TEST_COUNT in (3,4)
>SM> and DATETIME > 39814.0
>SM> and SCORE < 30
1) Do you have indices on the join fields?
2) Look at the ANALYZE command
3) Look at the EXPLAIN command
--
Piet van Oostrum <piet at cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org
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