KB2999809 - FIX: Poor performance when a query contains table joins in SQL Server 2014

Applies to: SQL Server 2014 EnterpriseSQL Server 2014 DeveloperSQL Server 2014 Standard


Assume that you run a query in Microsoft SQL Server 2014. The query contains table joins, and the related table has a Clustered Columnstore Index (CCI). In this situation, comparing to the earlier version of SQL Server, you may experience poor query performance because of missing CCI segment elimination.


This issue occurs because of a regression in SQL Server 2014. During a probe scan of a hash join, SQL Server does not use available information (bloom filter bitmap) to eliminate CCI segments.


The issue was first fixed in the following cumulative update of SQL Server.

Cumulative Update 1 for SQL Server 2014 SP1

Cumulative Update 8 for SQL Server 2014

Hotfix information

Hotfix for SQL Server 2014

This hotfix is included in the following hotfix package:


Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.