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how to reduce sort on order by?


how to reduce sort on order by?

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curious_sqldba
curious_sqldba
SSCrazy
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I have a query where sort is done at the end on different columns from 3 different databases. I see that in the execution plan most of the cost is around the sort , if all these columns were in one db i could have added as part of index but how this work when sort is done on multiple columns from different dbs? Sample code is below



GROUP BY Db1.UserName,
Db1.Email,
Db2.LocationID,
Db3.[Name]


GilaMonster
GilaMonster
SSC Guru
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I think there's something missing from your sample code.

In short, you can't really reduce the cost, sorts are expensive operations, if you need a sorted resultset, you have to accept the cost of sorting. With adequate memory and optimised TempDB, you may be able to reduce the time required to do the sort though.

Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

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