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Does the difference between the estimated and actual rows seem ok?

I am a looking at an nonclustered index node on my excution plan.

The estimated amount of rows = 15.
The actual amount of rows = 409.

My statistics were updated last night at 11:44.

Does the difference between the estimated and actual seem ok?
0
Mr_Shaw
Asked:
Mr_Shaw
4 Solutions
 
Raja Jegan RSQL Server DBA & ArchitectCommented:
Yes, it happens most of the times..
But its not desirable from our perspective and it shows the chances of improving or optimizing our query.
Even though our tables have appropriate indexes created, there might be chances that

1. Indexes are not properly utilized for execution of the query.
2. Statistics generated is not being used by the Query Optimizer

And the possible solutions that can be implemented are listed in this article clearly:
http://www.simple-talk.com/sql/performance/sql-server-statistics-problems-and-solutions/
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Aaron ShiloCommented:
LET ME ADD ONE MORE THING

the optimizer calculates the CARDINALITY and isent allways aqurate.

read more : http://msdn.microsoft.com/en-us/library/ms181034.aspx
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qasim_mdCommented:
Yes this is fine. Estimated is the no of rows that will be read with your query and Actual is the total number of rows in the table
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Anthony PerkinsCommented:
>>Estimated is the no of rows that will be read with your query and Actual is the total number of rows in the table <<
You may want to double check that.
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Mr_ShawAuthor Commented:
thanks
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