In SQL Server, updates and inserts are processed initially into a B-tree table called a delta store. Eventually, a process called a tuple mover compresses the data into the columnstore structure.

SQL Server 2012 includes a lot of new and exciting features. One feature that has caught the imagination of many in the user community is the high-performance feature called Columnstore Indexes.

This article explores the internals of Oracle9i indexing; reviews the standard b-tree index, index-only tables, and how these indexes may increase the speed of Oracle SQL queries.