Although this approach improves performance overall, under some conditions (for example, in the case of an inaccurate cardinality estimation that is related to parameter sensitivity), the scan-below filter may be processing a larger number of rows than expected. This fact may be hidden during query performance troubleshooting when you are using an actual execution plan, because the actual number of rows that is returned will correspond to the number of rows after the residual predicate is applied and not the actual number of rows that are scanned from a table or index.
This functionality was fist introduced in the following Service Packs for SQL Server.
bugs that are fixed in SQL Server 2012 Service Pack 3 .
About Service packs for SQL Server
Service packs are cumulative. Each new service pack contains all the fixes that are in previous service packs, together with any new fixes. Our recommendation is to apply the latest service pack and the latest cumulative update for that service pack. You do not have to install a previous service pack before you install the latest service pack. Use Table 1 in the following article for finding more information about the latest service pack and latest cumulative update.
How to determine the version, edition and update level of SQL Server and its components
ID articol: 3107397 - Ultima examinare: 8 dec. 2016 - Revizie: 1