The online index rebuild can cause index corruption or data loss when it is used together with concurrent queries that modify many rows in Microsoft SQL Server 2012 or Microsoft SQL Server 2014. For example, a replication updates many rows on a table when the online index build is running on the same table concurrently.
This issue occurs when the following conditions are true:
The online index build query runs in parallel mode.
Deadlock error and a fatal error such as "lock timeout" occur in a specific order.
Note To work around this issue, run the online index build in serial mode (DOP = 1).
Cumulative update information
The issue was first fixed in the following cumulative update of SQL Server.
Each new cumulative update for SQL Server contains all the hotfixes and all the security fixes that were included with the previous cumulative update. Check out the latest cumulative updates for SQL Server:
A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem.
If the hotfix is available for download, there is a "Hotfix Download Available" section at the top of this Knowledge Base article. If this section does not appear, submit a request to Microsoft Customer Service and Support to obtain the hotfix.
Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft website:
Note The "Hotfix Download Available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.
Note After you apply the hotfix, extended event progress_report_online_index_operation will additionally include error details in the error_number data field that has been added to the event. This field can be used to identify any internal failures during the Online Index operation.
You do not have to restart the computer after you apply this hotfix.
Hotfix replacement information
This hotfix does not replace a previously released hotfix.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.