Microsoft SQL Server supports isolation levels 0 (Read Uncommitted), 1 (Read Committed), 2 (Repeatable Read), and 3 (Serializable). Microsoft SQL Server supports row-level and table-level locking. See "Locking and Isolation Levels" for details.
Microsoft SQL Server 2005 and higher supports the following additional isolation levels:
Snapshot
Read Committed with Snapshots
Read Committed with Locks (equivalent to Read Committed in previous Microsoft SQL Server versions)