Revoking execute access on builtin functions on SQL Server I am trying to lock down a SQL Server database server and I want to revoke execute access from all users on specific builtin functions such as LEFT, RIGHT SUBSTRING, etc. 

When I try to execute:

REVOKE EXECUTE ON LEFT from appuser;


I get an error:


  Cannot find the object 'LEFT', because it does not exist or you do not have permission.


In addition, are there any other functions that can perform the same operation on SQL server, i.e. be used to extract portions of a static string ?

Thanks
You cannot restrict permissions to LEFT built-in function.
You can control permissions that are listed by the output of this command:

SELECT *
FROM fn_builtin_permissions(default)