Symptoms
Assume that you have Clustered Columnstore Index (CCI) on a table in Microsoft SQL Server 2016 or 2017. During clustered columnstore delete bitmap seek, if a concurrent query modifies the same bitmap, an assertion failure occurs.
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Resolution
This problem is fixed in the following cumulative updates for SQL Server:
About cumulative updates for SQL Server
Each new cumulative update for SQL Server contains all the hotfixes and security fixes that were in the previous build. We recommend that you install the latest build for your version of SQL Server:
Latest cumulative update for SQL Server 2017
Latest cumulative update for SQL Server 2016
References
Learn about the terminology that Microsoft uses to describe software updates.