[progress Communities] [progress Openedge Abl] Forum Post: Re: Simple Loop Is Slow Compared...

[George Potemkin]

Another example: In the self-service mode FOR EACH customer NO-LOCK WHERE TRUE : END. is almost twice slower than FOR EACH customer NO-LOCK WHERE FALSE : END. Both queries create exactly the same db activity. The difference: the query with WHERE FALSE does not copy the records from the so-called network buffers to the client's record pool. In other words, the time needed to copy a record from one part of the client's private memory to the another its part almost equals to the time needed to retrieve a record from shared memory using the locking protocols. Why this operation is much longer (tens times) than, for example, a latch lock?

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