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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-query will return the same record for all rows since the where clause (if any) is constant.

David J.
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