Snapshot Isolation Level in SQL Server - What, Why and How Part 2

Introduced in SQL Server 2005, Snapshot Isolation levels improve performance, however, there are some caveats to consider when using this feature. Some people use it frequently, as it minimizes blocking and improves performance/concurrency, without knowing its impact on maintaining versions in tempdb. Others stay away from it because of this extra overhead. Some people are confused by the two variants of snapshot isolation level (Read Committed Snapshot Isolation (RCSI) and Snapshot Isolation (SI)) and use one variant where the other is needed or vice versa. In my last article (Snapshot Isolation Level in SQL Server - What, Why and How – Part 1) I talked about basic of isolation levels and snapshot based isolation levels and how they differ from each other in terms of performance and cost; in this article I am going to demonstrate how to use these isolation levels with examples; for more information click here.