Thomas Beutin <[EMAIL PROTECTED]> writes: > i've a speed problem withe the following statement: > SELECT DISTINCT pz.l1_id, pz.l2_id, pz.l3_id, pz.l4_id > FROM ot_adresse AS a, ot_produkt AS p > LEFT OUTER JOIN ot_kat_prod AS pz ON ( p.p_id = pz.p_id ) > WHERE p.a_id = a.id AND a.id = '105391105424941' AND a.m_id = '37';
In 7.2 (and 7.3), this syntax forces the planner to join ot_produkt to ot_kat_prod first, which is terribly inefficient because the WHERE constraints don't constrain that join at all. You could work around this by writing instead FROM (ot_adresse AS a CROSS JOIN ot_produkt AS p) LEFT OUTER JOIN ot_kat_prod AS pz ON ( p.p_id = pz.p_id ) WHERE p.a_id = a.id AND a.id = '105391105424941' AND a.m_id = '37'; See http://www.postgresql.org/docs/7.3/static/explicit-joins.html for discussion. (Note: 7.4 will be less rigid about this issue.) regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 4: Don't 'kill -9' the postmaster
