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RR wrote:
>
> Hi all, I'm curious to know if anyone has tested the merge function or
> knows how it works more or less. Assuming that you are merging two
> identical tables with nearly identical values: Does it, when it finds
> a match, update all columns in that row, only columns that are
> different, or skip that row if there are no differences?
> I would assume the latter, but admittedly haven't tested it, so I was
> wondering if anyone knew the answer offhand.
>
Basically you write a merge statement with 3 parts:
the 'pretty much' comments indicate the syntax for that section is different, but recognizable, as derived from a traditional update/insert.
In other words, you tell it explicitly how to handle the update or insert.
(You might enjoy reading about it in the manual - it's pretty well documented. Anything short of your own research will likely give you an incorrect impression how it actually works.)
HTH/Hans Received on Fri Nov 07 2003 - 12:05:46 CST