Thanks and Regards Yan Cheng CHEOK --- On Tue, 1/26/10, Alban Hertroys <dalroi@xxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > From: Alban Hertroys <dalroi@xxxxxxxxxxxxxxxxxxxxxxxxxxxx> > Subject: Re: Primary Key Increment Doesn't Seem Correct Under Table Partition > To: "Yan Cheng Cheok" <yccheok@xxxxxxxxx> > Cc: pgsql-general@xxxxxxxxxxxxxx > Date: Tuesday, January 26, 2010, 6:36 PM > On 26 Jan 2010, at 11:00, Yan Cheng > Cheok wrote: > > > However, whenever I insert row into measurement table, > I realize its primary key value is going from 2, 4, 6, 8, > 10... > > > > May I know how can I prevent this? > > Apparently nextval on that sequence gets called multiple > times in your queries. > Do you have any idea why it happens so? > > Also, is it necessary to create index for > measurement_id found in measurement's child table? I am > concern on the read speed. > > > Serials don't create indexes, only a sequence. Primary keys > create indexes (to guarantee uniqueness) - foreign keys do > not. > So yes, you want an index on that column in the child > table. > But... measurement table does contains CONSTRAINT pk_measurement_id PRIMARY KEY (measurement_id), when measurement_0 child table inherits from measurement table, isn't it will inherit PRIMARY KEY (measurement_id)? Do I still have to create index for measurement_0.measurement_id ? > Alban Hertroys > > -- > Screwing up is the best way to attach something to the > ceiling. > > > !DSPAM:737,4b5ec59910605107914066! > > > > -- > Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-general > -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
