On Mar 22, 8:09 pm, p...@xxxxxxxxxxx (Jeff Davis) wrote: > On Tue, 2007-03-20 at 13:21 -0700, Angva wrote: > > Your Oracle solution is interesting, and can indeed be implemented in > PostgreSQL in exactly the same way. Look at materialized views here: > > http://www.varlena.com/varlena/GeneralBits/Tidbits/matviews.html > > Another way to do it without using an entire materialized view is to > obtain a row level lock on the ID using SELECT ... WHERE id=123 FOR > UPDATE. To do this you need to have a table that contains all the IDs > and where id has a unique index to prevent race conditions when adding > new IDs. > > What are you trying to do exactly? Why does the table have no primary > key? Thanks for that info. The materialized view functions look a bit unwieldy for this one purpose...Your other idea might be simpler to implement. What I'm trying to accomplish...I'm dealing with financial accounts, each of which has a purchase limit of $x, and one or more sub- accounts. Each sub-account is allocated a percentage of this limit. So account A could have sub-accounts 1, 2 and 3, with 50%, 30% and 20% respectively allocated. Or there could be just one sub-account with exactly 100%. The "real" table actually does have a primary key - I was using a simplified example to make my point. Thanks for your input, Mark
