FIX: Rebuilding a nonclustered index to add columns by using CREATE INDEX with DROP_EXISTING=ON and ONLINE=ON causes blocking


You rebuild a non-clustered index by using CREATE INDEX together with the DROP_EXISTING=ON and ONLINE=ON clauses to add a new column to that non-clustered index in SQL Server. If you add a new column to the nonclustered index, you may encounter blocking in a different SPID when write operations such as INSERT or DELETE are performed on the same underlying table during the index rebuild period.


Update information

This issue is fixed in the following cumulative updates for SQL Server:

Cumulative Update 6  for SQL Server 2012 Service Pack 3

Cumulative Update 10 for SQL Server 2014 SP1  

Cumulative update 3 for SQL Server 2014 SP2

Cumulative Update 4 for SQL Server 2016

Recommendation: Install the latest cumulative update for SQL Server


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


Learn about the terminology that Microsoft uses to describe software updates.

Article ID: 3194365 - Last Review: 18 Jan 2017 - Revision: 3