Hi, Explain my sql querry :
Limit (cost=1057.15..1057.16 rows=1 width=27) -> HashAggregate (cost=1057.15..1057.16 rows=1 width=27) -> Nested Loop (cost=0.00..1057.14 rows=1 width=27) -> Seq Scan on stat a (cost=0.00..1042.98 rows=1 width=8) Filter: (((month)::double precision = date_part('month'::text, (now() - '1 mon'::interval))) AND ((year)::double precision = date_part('year'::text, (now() - '1 mon'::interval)))) -> Index Scan using resaller_pkey on revendeur b (cost=0.00..14.15 rows=1 width=23) Index Cond: ("outer".idxresaller = b.idxresaller) Filter: (asp = 6) I would optimize "Seq Scan on stat a (cost=0.00..1042.98 rows=1 width=8)" What is your advice ? Thank you Stan 2007/9/14, A. Kretschmer <[EMAIL PROTECTED]>: > am Fri, dem 14.09.2007, um 10:31:39 +0200 mailte Stanislas de Larocque > folgendes: > > Hi, > > > > I want to optimize my qerry sql (execution time : 2448 ms) : > > > > SELECT b.idxreseller, sum(a.nbrq), b.namereseller from stat a > > ,reseller b where b.asp=6 and a.idxreseller=b.reseller and > > a.month=date_part('month',now() - interval '1 month') and > > a.year=date_part('year',now() - interval '1 month') GROUP BY > > b.idxreseller,b.namereseller limit 15; > > Show us the output from EXLAIN ANALYSE <your query>. > > My guess: you need at least an index in reseller.asp. Why do you have > columns such a.month and a.year? se a regular DATE or TIMESTAMPTZ field > instead and an index on this. > And use CURRENT_DATE instead now(). > > Andreas > -- > Andreas Kretschmer > Kontakt: Heynitz: 035242/47150, D1: 0160/7141639 (mehr: -> Header) > GnuPG-ID: 0x3FFF606C, privat 0x7F4584DA http://wwwkeys.de.pgp.net > > ---------------------------(end of broadcast)--------------------------- > TIP 9: In versions below 8.0, the planner will ignore your desire to > choose an index scan if your joining column's datatypes do not > match > ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match