Columnstore index is part of In-Memory technologies released in SQL Server 2014 and SQL Server 2016. Please refer to https://blogs.msdn.microsoft.com/sqlserverstorageengine/tag/columnstore-index/ for a series of blogs on columnstore index. As the name In-Memory Analytics implies, you may think that columnstore index is entirely memory resident but it is not really the case for columnstore indexes created on...