isql Utility

The isql utility allows you to enter Transact-SQL statements, system procedures, and script files; and uses DB-Library to communicate with Microsoft® SQL Server™ 2000.

 

http://msdn2.microsoft.com/en-us/library/Aa214007(SQL.80).aspx

 

This is handy if you don't have access to any other tools for testing SQL queries, which in most cases is probably rare, but still, it's nice to have other options available just in case.