Posts tagged "performance"

Variable Size Data Types and Memory Grants

Posted by Ami Levin on Tuesday, 08 May 2012

Yesterday, at our 118th Israeli SQL Server User Group Meeting, Adi Cohn delivered a session on common performance pitfalls. One of the issues he mentioned is something every DBA and database designer should be aware of. Many applications use overly large size limit for their variable data types. The reasoning in many cases is simply "Why not?" If you have a variable size column and you made the choice to use one of the VAR data types anyway, why limit the size? Even if you expect to have up to 300 characters in the 'comments' column for example, what is wrong with defining it as 3,000? it's just metadata, right? Wrong...

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Index rebuilds and statistics updates

 Posted by Ami Levin on Wednesday, 25 April 2012

An interesting discussion came up lately on the MVP private forums regarding index rebuilds,recompilation and statistics updates. Although the debate spanned too many aspects for me to cover here in this short post, I think that one important point should be emphasized as it might be making you do redundant work or even worse - unknowingly degrade the performance of your workload.

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