Why are Op Stats all 0's and yet Usage Stats show 29 seeks. This was returned from Brent Ozar's sp_blitzindex.
Usage Stats Op Stats Reads: 29 (29 seek) Writes:14 0 singleton lookups; 0 scans/seeks; 0 deletes; 0 updates;
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2Have you tried finding the answer by looking into the source code to see how the SP retrieves both groups of stats?– Andriy MMay 26, 2016 at 6:29
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1 Answer
Usage statistics come from sys.dm_db_index_usage_stats, which tracks the number of execution plans that include an operator touching that index. It's reset on SQL Server service restart, or when the index is modified.
Operational statistics come from sys.dm_db_index_operational_stats, which track the number of times the index has actually been touched. It's reset on a different schedule - when that object's metadata disappears from cache.
answered May 26, 2016 at 11:06
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Thanks Brent. I also found this more detailed explanation: msdn.microsoft.com/en-us/library/ms174281.aspx#Anchor_4– David GMay 26, 2016 at 20:48