It's a typical non-sargable query. This means that the WHERE clause (or at least part of it) of the query cannot take advantage of an index, instead performing a table/index scan, which may cause the query's performance to suffer.
If you currently have a query that uses NOT IN, which offers poor performance because the SQL Server optimizer has to use a nested table scan to perform this activity, instead try to use one of the following options instead, all of which offer better performance:
-Use EXISTS or NOT EXISTS
-Use IN
-Perform a LEFT OUTER JOIN and check for a NULL condition
You can find more in:
If you currently have a query that uses NOT IN, which offers poor performance because the SQL Server optimizer has to use a nested table scan to perform this activity, instead try to use one of the following options instead, all of which offer better performance:
-Use EXISTS or NOT EXISTS
-Use IN
-Perform a LEFT OUTER JOIN and check for a NULL condition
You can find more in: