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SQL Profiler Reads vs Set Statistics IO logical reads Expand / Collapse
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Posted Monday, December 10, 2012 11:56 AM
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I created a table with a single varchar(10) column and ran a select statement against it. In Profiler, it shows 25 reads but in SSMS using Statistics IO, it shows only 1 logical read. What is the difference between the two values? Also, I did the same thing against another SQL 2005 server and the reads in Profiler show only 3 and I'm trying to figure out why one shows 3 and one shows 25 for such a simple statement. The table has no triggers, indexes.

Thanks.
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Posted Monday, December 10, 2012 12:15 PM
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more information: I found out that on the server with greater reads, it always generates a CacheInsert event, but on the server with lesser reads, it generates a CacheHit event. Maybe that's the cause of the extra reads. Further, the procedure cache hit ration is very low (20%) and the cache size is small (only a few MB). so now my question is - why is the query plan not being written to cache (or aged out immediately).
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