thanks a lot for the tip! sorry for used the wrong word, it is just multi-master but not sharding, I would like to setup two master server across two datacenter. one's id increased by 1, and the other by 2. so I could have a queue sync the record in the background by myself. kind of a dumb way but it seems they only choice for me, the delay within several minutes is acceptable.
On Tue, Nov 15, 2011 at 5:12 PM, John R Pierce <pie...@hogranch.com> wrote: > On 11/15/11 12:56 AM, Bèrto ëd Sèra wrote: > >> Hi >> >> >> On 15 November 2011 11:44, Yan Chunlu <springri...@gmail.com <mailto: >> springri...@gmail.com>**> wrote: >> >> I would like to implement two master db with even-odd id sharding. >> in mysql it is fairly easy by using the configuration: >> >> auto_increment_offset = 1 >> auto_increment_increment = 2 >> >> >> but I have searched a lot didn't find anything related to this, >> some users doing this via trigger like "rubyrep". >> >> is there an easy way to do this? thanks! >> >> >> http://www.postgresql.org/**docs/8.1/static/sql-**createsequence.html<http://www.postgresql.org/docs/8.1/static/sql-createsequence.html> >> >> >> > also see ALTER SEQUENCE. > > basically, you'll need to fix up every sequence (these are created > automatically if you have fields of type SERIAL).... on your 2nd server, > > ALTER SEQUENCE somesequencename INCREMENT BY 2 RESTART WITH 2; > > and on your 1st server, > > ALTER SEQUENCE somesequencename INCREMENT BY 2; > > do this before inserting any data. > > thats a fairly unusual sharding technique, how do you plan on doing > queries across both sets of data? > > > -- > john r pierce N 37, W 122 > santa cruz ca mid-left coast > > > > -- > Sent via pgsql-general mailing list (pgsql-general@postgresql.org) > To make changes to your subscription: > http://www.postgresql.org/**mailpref/pgsql-general<http://www.postgresql.org/mailpref/pgsql-general> >
