Easytrieve Not Equal Operator (<>)

Basic Syntax

Not equal appears between operands in conditional expressions: IF STATUS <> T, IF GROSS <> 0, IF NEW-KEY <> OLD-KEY. True when values differ; false when they compare equal under type rules. Use in IF ELSE-IF DO WHILE and nested conditions. Does not modify operands.

1
2
3
4
5
6
7
8
JOB INPUT PAYROLL
  IF ERROR-CODE <> 0
     PRINT EXCEPTION-RPT
  END-IF
 
  IF NEW-GROSS <> PRIOR-GROSS
     PRINT CHANGE-RPT
  END-IF

<> Versus NE

IF STATUS NE X and IF STATUS <> X are equivalent in standard grammar. Choose one style per program section for maintainability. Code reviewers scanning for NE find all relational tests quickly when you avoid mixing six symbolic and six keyword forms randomly.

Numeric Not Equal

IF BALANCE <> 0 includes positive and negative non-zero balances—only exact zero fails the inequality. IF TAX <> FED-TAX flags rows where two tax fields diverge. Packed decimal compares by value: 10.00 <> 10.01 is true at P 2 scale. Watch implied decimal alignment when comparing P 2 to N 5—values that display the same may still compare unequal internally if conversion differs. Zero versus LOW-VALUES: uninitialized packed fields may not equal business zero—validate FILE data before trusting <> 0 as valid record test.

Alphabetic Not Equal

IF REGION <> 99 excludes region ninety-nine when REGION is N 2 or A 2 depending on definition. IF NAME <> PRIOR-NAME detects name changes between history and current file merge. Trailing spaces cause false inequality: ARNOLD-space versus ARNOLD-space on equal-length fields compares equal; ARNOLD-space versus ARNOLD literal may compare unequal if literal padding differs. Trim or normalize before <> when business rules ignore blanks.

Exclusion Filters Versus Inclusion

Inclusion: IF DEPT = 911 keeps one department. Exclusion: IF DEPT <> 999 keeps every department except 999. When valid codes are few, equality lists are shorter. When one bad code must drop, not equal is clearer than long OR chains of allowed equals. Multiple exclusions: IF CODE <> X AND CODE <> Y AND CODE <> Z—or refactor to positive allow-list with equality and OR when codes are enumerable.

Change Detection Pattern

Prior-cycle compare files drive reconciliation jobs. IF CURR-AMT <> PRIOR-AMT PRINT CHANGE-RPT highlights adjustments. Sort both files by key, read in parallel or merge pattern, compare field by field with <>. Pair with = for no-change skip: IF CURR-AMT = PRIOR-AMT skip detail PRINT when only exceptions matter—reduces spool volume.

1
2
3
4
5
6
7
8
9
JOB INPUT MASTER
  IF RECORD-STATUS <> 'A'
     PRINT INACTIVE-RPT
  END-IF
 
  IF ZIP-CODE <> PRIOR-ZIP
     MOVE ZIP-CODE TO PRIOR-ZIP
     PRINT ADDRESS-CHANGE-RPT
  END-IF

Combining With Logical Operators

IF STATUS <> X AND STATUS <> Y requires both inequalities—status differs from X and from Y. IF TYPE <> A OR TYPE <> B is almost always true for any TYPE value—a common logic bug; beginner meant AND or a single not-equal against a set. IF NOT DEPT = 911 equals IF DEPT <> 911 when NOT applies to the equality subexpression. Parentheses prevent surprises: IF (A <> B) AND (C <> D).

Not Equal Versus Greater or Less

Inequality <> only tests difference—not ordering. IF AGE <> 18 includes ages below and above eighteen. IF AGE GT 18 excludes minors only. Pick operator matching business rule wording. Auditors asking for everyone not exactly sixty-five need <> 65 or NOT = 65, not GT 65 alone.

Performance Considerations

Single <> compare per record is inexpensive. Long chains of AND <> on many literals cost more in maintenance than lookup table or range design. Consider E-Z Table or site validation patterns when excluding dozens of codes—architecture choice beyond operator mechanics but affects nightly batch CPU when IF trees grow deep.

Common Not Equal Mistakes

• IF A <> B OR A <> C when AND was intended.
• Expecting <> to test ordering magnitude.
• Ignoring space padding on alphabetic compares.
• Comparing uninitialized FILE numeric to zero without validation.
• Mixing <> and NE without team convention.
• Using <> for assignment—invalid context.

Explain It Like I'm Five

Not equal means not the same. If everyone wearing a red hat goes to circle A, not equal red sends everyone else—blue hats, green hats, no hats—to circle B. The <> sign is a way of saying these two things do not match. It is the opposite of asking are they the same? Spelling NE means the same thing as <>—like saying isn't instead of is not. Be careful when you say not red and not blue—you might accidentally include almost everyone unless you really mean both rules at once.

Exercises

1. Write exception filter IF ERR <> 0 with PRINT.
2. Rewrite IF NOT STATUS = X as IF STATUS <> X.
3. Explain why IF A <> 1 OR A <> 2 is usually always true.
4. Build change-detection IF NEW <> OLD for one amount field.
5. Compare when to use DEPT = 911 versus DEPT <> 999 for business filtering.