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SQL Server Support Blog
4 MIN READ

The case of the filter predicate with window functions such as ROW_NUMBER and RANK

Troy Moen's avatar
Troy Moen
Icon for Microsoft rankMicrosoft
Apr 25, 2019
I recently helped troubleshoot a query performance issue that involved the window function "ROW_NUMBER". The running theory was that the query’s filter predicate should target the index resulting in ...
Updated Apr 25, 2019
Version 3.0
performance
Storage Engine
troubleshooting
TSQL
g_keramidas's avatar
g_keramidas
Brass Contributor
Apr 25, 2019

I have a performance issue i'd like to report. how do I do it? I can do a simple find through a list and it takes .3 seconds to complete (that's point 3). if I add conditional formatting->duplicate values to the column, the find time increases to over 35 seconds to complete. over 100 times slower.