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 Help on Optimization  [new]
JoeClark
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Hello,

When looking at the sql plan, it shows that a "Hash Match (Union)" has a cost of 88%. Looking at the code, it is a union and not a "union all". One of the union statements then is followed by a "select distinct", which seems to be redundant, if you aren't using a union all.

In general, it appears from my searching that a hash match (union) can indicate an inefficient statement. Any suggestions/thoughts on what to look for? We have done just about all the indexes we can try -- so now I am trying to figure out what to recommend the vendor to change on his stored procedure.

I have access to the stored procedure.

Thanks for any help anyone can provide.

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Сообщение было отредактировано: 1 июл 17, 12:12
1 июл 17, 11:25    [20604931]     Ответить | Цитировать Сообщить модератору
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