Expression Fundamentals

Expressions evaluate to values of PeopleCode data types. A simple PeopleCode expression can consist of a constant, a temporary variable, a system variable, a record field reference, or a function call. Simple expressions can be modified by unary operators (such as a negative sign or logical NOT), or combined into compound expressions using binary operators (such a plus sign or logical AND).

Definition name references evaluate to strings equal to the name of a PeopleTools definition, such as a record or page. They enable you to refer to definitions without using string literals, which are difficult to maintain.

Metastrings (also called meta-SQL) are special expressions used within SQL string literals. At runtime, the metastrings expand into the appropriate SQL for the current database platform.