SQL expressions generally use the syntax of the database instead of Crystal syntax (there are some exceptions, though...)  They also have to be written using a field/fields from one or more tables that have already been added to the report using the same schema_owner.table_name.field syntax that Crystal uses for its query, which is what you get when you double-click on the field name in the SQL Expression Editor.

 

You cannot do a select statement in a SQL Expression.  If you need a field from a table that's not included on the report, you need to go to the Database Expert and add the table to the report that way either by selecting it or by adding a command through the Database Expert.

 

-Dell