Left joins on DataSets

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Feek - 20 Apr 2007 17:54 GMT

I have some tables from a proprietary ODBC source that I read into Datasets.
Because of limitations on this source, only a single LEFT JOIN can be used at
a time in the SQL to fill the Datasets. What I'd like to do is to take two
Datasets created from LEFT JOIN statements, and LEFT JOIN those to make
another Dataset that would basically have all the information it would have
if I was able to do multiple JOINs.

What's the recommended way to do this...just using regular loops is making
the program run way too slow. Right now it's at 30 minutes, and I need it
under 5.

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Feek - 20 Apr 2007 17:56 GMT

P.S. Please let me know if this is in the wrong group.

> I have some tables from a proprietary ODBC source that I read into Datasets.
> Because of limitations on this source, only a single LEFT JOIN can be used at
[quoted text clipped - 6 lines]
> the program run way too slow. Right now it's at 30 minutes, and I need it
> under 5.

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Alvin Bruney [MVP] - 22 Apr 2007 21:15 GMT

hmmm, regular loops would work but that's kinda tedious. If your database
supports it, you should do it by creating a temp table or a sub query. That
would give you the joined dataset. If the dataset does not support it, you
can create a temporary dataset and merge the two datasets into one using
filters. That's a lot of work though.

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Regards,
Alvin Bruney
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> P.S. Please let me know if this is in the wrong group.
>
[quoted text clipped - 13 lines]
>> the program run way too slow. Right now it's at 30 minutes, and I need it
>> under 5.

Reply to this Message

Left joins on DataSets

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