Topics:

• Types of Expressions You Can Write
• Writing Numeric Expressions
• Writing Date Expressions
• Writing Date-Time Expressions
• Writing Alphanumeric Expressions
• Writing Logical Expressions
• Writing Conditional Expressions
• Handling Null Values in Expressions

An expression enables you to combine variables, constants, operators, and functions in an operation that returns a single value. Expressions are used in a wide variety of Maintain commands. You can build increasingly complex expressions by combining simpler ones.

Expressions in Maintain are similar to expressions in other FOCUS facilities, but some behavior and rules differ, and some functionality is enhanced.