I have a table that looks like this... Index (self incrementing number), Address (string), Transaction (string), Amount (probably long)
What I need to do is enforce a rule that a given combination of address and transaction must be unique without making either Address or Transaction, individually unique. Ideally I would like to do something along the lines of SELECT SUM(Amount) FROM Transactions WHERE Address='someaddress'; The problem that I'm facing is that there is a non zero probability that two or more worker units could be trying to insert the same transaction/address at the same time. These would also have the same amounts. Under this table layout, the double insert would stick in two rows. Somehow I need to constrain the pair. I guess I could concatenate Address+Transaction and force that to be unique. Then replace the query statement with SELECT SUM(Amount) FROM Transactions WHERE Chimera LIKE(Address); But as you can tell from my naming the field Chimera, that solution just doesn't sit right. Any of you DB pros have a possibly better solution? Thanks! /* PLUG: http://plug.org, #utah on irc.freenode.net Unsubscribe: http://plug.org/mailman/options/plug Don't fear the penguin. */
