On 13/01/2010 4:09 PM, Yan Cheng Cheok wrote:
I have 3 tables - lot, unit and measurement
1 lot is having relationship to many unit.
1 unit is having relationship to many measurement.
delete cascade is being used among their relationship
SemiconductorInspection=# delete from lot where lot_id = 2;
Are there indexes on fk_lot_id and fk_unit_id ? If not, a DELETE from
lot will cause a seqscan of unit for affected units, and if any must be
deleted each will cause a seqscan of measurement for affected
measurements. That's going to get ugly fast.
--
Craig Ringer
--
Sent via pgsql-general mailing list (pgsql-general@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-general