Greetings,<BR><BR>I've used "WHERE 1=1" for a long time in dynamic where clauses in which every condition is optional, and lately I heard it suggested that this can cause full table scans by itself.

Read this SQL tutorial to learn when to use SELECT, JOIN, subselects and UNION to access multiple tables with a single statement. It’s sometimes difficult to know which SQL syntax to use when ...

Note: Unlike a SYSTEM 2000 where-clause stored in a view descriptor, a SAS WHERE clause is restricted to variables corresponding to items included in the view descriptor. (A SYSTEM 2000 where-clause ...