Re: UPDATE using query; per-row function calling problem

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От David Johnston
Тема Re: UPDATE using query; per-row function calling problem
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Msg-id D24E1FBC-7C5D-4455-9E69-46EB35EC4D61@yahoo.com
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Ответ на Re: UPDATE using query; per-row function calling problem  (Rory Campbell-Lange <rory@campbell-lange.net>)
Ответы Re: UPDATE using query; per-row function calling problem
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>
> In my "-1" example, am I right in assuming that I created a correlated
> subquery rather than an correlated one? I'm confused about the
> difference.
>
>

Correlated: has a where clause that references the outer query
Un-correlated: not correlated

Because of the where clause a correlated sub-query will return a different record for each row whereas an un-correlated
sub-querywill return the same record for all rows since the where clause (if any) is constant. 

David J.

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