PRB: Zero Rows Returned from SQL SELECT Statement

ID: Q59461

The information in this article applies to:

Microsoft SQL Server versions 4.2x, 6.0, 6.5, 7.0

SYMPTOMS

Executing the following SQL statement returns 0 (zero) rows:


   select t1.* from t1,t2

"t1" has key values of 1, 2, 3, and 4; "t2" is empty.

CAUSE

The above statement does not return any rows because when you specify two tables in the same SELECT statement without a WHERE qualifier, the result is a Cartesian product. However, a Cartesian product with one table empty is 0 rows. This is the same as multiplying any number by 0: the result is 0.

Additional query words: Transact-SQL Windows NT

Keywords : kbother SSrvGen SSrvTrans SSrvWinNT
Version : winnt:4.2x,6.0,6.5,7.0
Platform : winnt
Issue type :