KB3053960 - FIX: A system assertion in longrec.inl:1318 occurs when you rebuild or create an index on a table in SQL Server 2012

Applies to: SQL Server 2012 DeveloperSQL Server 2012 EnterpriseSQL Server 2012 Standard


Assume that you have a table that contains a FILESTREAM column and a LOB column in Microsoft SQL Server 2012. When you drop the LOB column, and try to rebuild an existing clustered index or create a new clustered index, you receive the following system assertion error message: 
<Date> <Time> spid<ID> Error: 17066, Severity: 16, State: 1.
<Date> <Time> spid<ID> SQL Server Assertion: File: <<FilePath>\longrec.inl>, line=1318 Failed Assertion = 'outBufLen >= offsetof (InRowContent, m_varBlobCol) + inBufLen'. This error may be timing-related. If the error persists after rerunning the statement, use DBCC CHECKDB to check the database for structural integrity, or restart the server to ensure in-memory data structures are not corrupted.
<Date> <Time> spid<ID> Error: 3624, Severity: 20, State: 1.
<Date> <Time> spid<ID> A system assertion check has failed. Check the SQL Server error log for details. Typically, an assertion failure is caused by a software bug or data corruption. To check for database corruption, consider running DBCC CHECKDB. If you agreed to send dumps to Microsoft during setup, a mini dump will be sent to Microsoft. An update might be available from Microsoft in the latest Service Pack or in a QFE from Technical Support.


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

Cumulative Update 6 for SQL Server 2012 SP2


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