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The database compatibility level applies to the whole database. You can see the CL of your databases easily: SELECT name , compatibility_level FROM sys.databases; For differences between the compatibility levels, have a look at the [ALTER DATABASE Compatibility Level documentation][1]. As you can see from that, when you change the compatibility level, stored procedures will get recompiled to use the features of that level. What you might be thinking about is how to identify features that are going to be unsupported. If this is the case, then have a look at the Deprecated Features counters: SELECT * FROM sys.dm_os_performance_counters WHERE object_name = 'SQLServer:Deprecated Features'; This will show (instance-wide) which features are being used on that server that are due to become unsupported at some point in the future. If you want to compare that list / get more details, then check out the [Deprecated Database Engine Features lists][2] [1]: https://msdn.microsoft.com/en-us/library/bb510680.aspx [2]: https://msdn.microsoft.com/en-us/library/ms143729.aspx