Different from (!= or <>)

The != operator checks for non-equality of two expressions or for two record variables. The <> can be used as alias for !=.

Syntax 1: Expression comparison

expr != expr
  1. expr can be any expression supported by the language.
  2. <> can be used as alias for !=.

Syntax 2: Record comparison

record1.* != record2.*
  1. record1 and record2 are records with the same structure.
  2. <> can be used as alias for !=.

Usage

The != operator evaluates whether two expressions or two records are different.

Note:

A less-than sign followed by a greater-than sign (<>) can be used as an alias for the != operator.

This operator applies to expressions that evaluate to primitive data types such as INTEGER, VARCHAR, DATE. It does not apply to the BYTE and TEXT types.

When comparing simple expressions (expr != expr), the result of the operator is NULL when one of the operands is NULL.

When comparing two records with the second syntax, the runtime system compares all corresponding members of the records. If one pair of members are different, the result of the operator is TRUE. When two corresponding members are NULL, they are considered as equal. This second syntax allows you to compare all members of records, but records must have the same structure.

Example

MAIN
  DEFINE n INTEGER
  LET n==512
  IF n!=32 THEN
     DISPLAY "The variable is not equal to 32."
  END IF
END MAIN