By the way, they say in BOL 2008:

Each Transact-SQL statement should be terminated with a semicolon. This requirement is not enforced, but the ability to end a statement without a...

Yes, question is instrustive (for me), but BOL says:

Caution:

Any null values returned by subquery or expression that are compared to test_expression using IN or NOT IN return UNKNOWN....

Duncan Pryde (7/5/2010)

Looks like a compatibility level issue. If you set the database to SQL Server 2000 compatibility mode, you lose the backslash character (92) from the list. Something to...

My Count is only 20 (while right answer is 21)! Here is text result of the query from Question:

Count String

----------- -----------

20 ...