G
George Potemkin
Guest
> a simple FOR EACH customer NO-LOCK does indeed make it about 4x faster. I also run the tests with kill -9. The probability that a session running "FOR EACH customer" will die with a latch lock was only 2-5 % (I don't remember an exact number). In other words the most of the time the session does not use the structures in the shared memory. > The WHERE FALSE seems a curiosity which doesn't have a lot to do with real world requirements. The functions in WHERE clause that are resolved on a server side are often used in the real applications. They might decrease a network traffic, let's say, by 50 or 90% while WHERE FALSE clause decreases the traffic by 100% (up to the absolute zero). But my point was: WHERE FALSE simply allows us to measure the time needed to copy the records from network buffers to the client's record pool (the small -l parameter) and this time seems to be too large.
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