On Wed, 23 Jul 2003, Jenny - wrote: > Iam trying to acquire rowlevel locks in postgresql. I try doing this: > 'select * from students where name='Larry' for update; > But by looking at the holding array of proclock , I've noticed that by doing this > only > AccessShareLock gets acquired which is a table level lock. How do I acquire > rowlevelock and > what fields of Lock or Proclock datastructures indicate it. Thanks Jenny
Hi Jenny, have you read up on the locking methods of postgresql in the documentation? Since postgresql uses an MVCC locking mechanism, locks in postgresql aren't really the same as they are in row locking databases like db2. If you set the default transaciton isolation mode in postgresql.conf to serializable, and wrap all your work in transactions, then select for update should do what you're wanting, but, of course, it's always good to crank up two psql monitors and actually prove it to yourself. :-) ---------------------------(end of broadcast)--------------------------- TIP 2: you can get off all lists at once with the unregister command (send "unregister YourEmailAddressHere" to [EMAIL PROTECTED])