i'm sorry but you are wrong...it produces a long-term performance gain. if you have a 100 clients, yes you will need to custom build some admin interface -- you will also want one if you're using a single table, and have a jumble of messages in it. Also, with one possibly large and much sought after table, if any client mis-behaves and slows things down, all clients will suffer. you also need to be very careful when administering messages for one client as not to affect others and corrupt their data too. Scalability? if your prog is modular enough you can farm out client tables to separate databases on separate boxes. One other thing that can be done to improve performance is to have a "already read" field that you check for when retrieving messages, and only every now and then delete all those "already read" messages in one update query, so the rdbms is not shuffling data every time you take off a message from the table. The data contention issue is the most likely bottleneck you will encounter with your current design. as the number of clients grows, performance will drop very quickly for each new client addition. sometimes you do need to de-normalize your data to suit real world applications. in fact, relational theory calls for de-normalization after first normalizing your data, if that is necessary. in this case, it is.

In reply to Re: Re: Re: Database poller by aquarium
in thread Database poller by Marcello

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