On 10/15/07, Syan Tan <kittylitter@xxxxxxxxxxxxx> wrote: > >Also keep in mind that MVCC is not the only way to implement > >transactions; pure locking is more common in other databases. In the > >locking model, most transactions prevent others from writing until > >after they are finished. Rows simply can't have different versions > >(and of course concurrent performance is awful). > > what about postgresql doing something like snapshot isolation level as per > the enemy M$ ? SQL Server is normally a pure locking database; from what I can tell, its snapshot isolation level adds a limited form of MVCC above that, making its concurrent behavior closer to PostgreSQL's: http://msdn2.microsoft.com/en-us/library/ms345124(d=printer).aspx ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
