Re: IS NOT NULL and LEFT JOIN

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Laurent Martelli <laurent.martelli@xxxxxxxxxxxx> writes:
> Do we agree that both queries are identical ?

No, they *aren't* identical.  Go consult any SQL reference.  Left join
conditions don't work the way you seem to be thinking: after the join,
the RHS column might be null, rather than equal to the LHS column.

			regards, tom lane


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