Handling Nested Query Literals so they are not used in the Main SELECT''s GROUP BY Statement

In a SQL Server Query we sometimes have nested Queries, and those Queries use the Value from the outer select statement, but if these values are used in the Group By, it could return more records than we are expecting.

The following example shows how to handle these types of Queries while staying away from the Group By.

Select (Select Col1 from Table2 where Col3=Table1.Col3) as Col1, Col2 from Table1 where Col4=1 Group by Col2, Col3
The above will return more records.

What we do is wrap our column in a max() or min(). Using this method, we no longer have to use the Col3 in the Group By.
Select (Select Col1 from Table2 where Col3=min(Table1.Col3)) as Col1, Col2 from Table1 where Col4=1 Group by Col2