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COBOL – Conditional Statements ”; Previous Next Conditional statements are used to change the execution flow depending on certain conditions specified by the programmer. Conditional statements will always evaluate to true or false. Conditions are used in IF, Evaluate, and Perform statements. The different types of conditions are as follows − IF Condition Statement Relation Condition Sign Condition Class Condition Condition-Name Condition Negated Condition Combined Condition IF Condition Statement IF statement checks for conditions. If a condition is true, the IF block is executed; and if the condition is false, the ELSE block is executed. END-IF is used to end the IF block. To end the IF block, a period can be used instead of END-IF. But it is always preferable to use END-IF for multiple IF blocks. Nested-IF − IF blocks appearing inside another IF block. There is no limit to the depth of nested IF statements. Syntax Following is the syntax of IF condition statements − IF [condition] THEN [COBOL statements] ELSE [COBOL statements] END-IF. Example Live Demo IDENTIFICATION DIVISION. PROGRAM-ID. HELLO. DATA DIVISION. WORKING-STORAGE SECTION. 01 WS-NUM1 PIC 9(9). 01 WS-NUM2 PIC 9(9). 01 WS-NUM3 PIC 9(5). 01 WS-NUM4 PIC 9(6). PROCEDURE DIVISION. A000-FIRST-PARA. MOVE 25 TO WS-NUM1 WS-NUM3. MOVE 15 TO WS-NUM2 WS-NUM4. IF WS-NUM1 > WS-NUM2 THEN DISPLAY ”IN LOOP 1 – IF BLOCK” IF WS-NUM3 = WS-NUM4 THEN DISPLAY ”IN LOOP 2 – IF BLOCK” ELSE DISPLAY ”IN LOOP 2 – ELSE BLOCK” END-IF ELSE DISPLAY ”IN LOOP 1 – ELSE BLOCK” END-IF. STOP RUN. JCL to execute the above COBOL program − //SAMPLE JOB(TESTJCL,XXXXXX),CLASS = A,MSGCLASS = C //STEP1 EXEC PGM = HELLO When you compile and execute the above program, it produces the following result − IN LOOP 1 – IF BLOCK IN LOOP 2 – ELSE BLOCK Relation Condition Relation condition compares two operands, either of which can be an identifier, literal, or arithmetic expression. Algebraic comparison of numeric fields is done regardless of size and usage clause. For non-numeric operands If two non-numeric operands of equal size are compared, then the characters are compared from left with the corresponding positions till the end is reached. The operand containing greater number of characters is declared greater. If two non-numeric operands of unequal size are compared, then the shorter data item is appended with spaces at the end till the size of the operands becomes equal and then compared according to the rules mentioned in the previous point. Syntax Given below is the syntax of Relation condition statements − [Data Name/Arithmetic Operation] [IS] [NOT] [Equal to (=),Greater than (>), Less than (<), Greater than or Equal (>=), Less than or equal (<=) ] [Data Name/Arithmetic Operation] Example Live Demo IDENTIFICATION DIVISION. PROGRAM-ID. HELLO. DATA DIVISION. WORKING-STORAGE SECTION. 01 WS-NUM1 PIC 9(9). 01 WS-NUM2 PIC 9(9). PROCEDURE DIVISION. A000-FIRST-PARA. MOVE 25 TO WS-NUM1. MOVE 15 TO WS-NUM2. IF WS-NUM1 IS GREATER THAN OR EQUAL TO WS-NUM2 THEN DISPLAY ”WS-NUM1 IS GREATER THAN WS-NUM2” ELSE DISPLAY ”WS-NUM1 IS LESS THAN WS-NUM2” END-IF. STOP RUN. JCL to execute the above COBOL program − //SAMPLE JOB(TESTJCL,XXXXXX),CLASS = A,MSGCLASS = C //STEP1 EXEC PGM = HELLO When you compile and execute the above program it produces the following result − WS-NUM1 IS GREATER THAN WS-NUM2 Sign Condition Sign condition is used to check the sign of a numeric operand. It determines whether a given numeric value is greater than, less than, or equal to ZERO. Syntax Following is the syntax of Sign condition statements − [Data Name/Arithmetic Operation] [IS] [NOT] [Positive, Negative or Zero] [Data Name/Arithmetic Operation] Example Live Demo IDENTIFICATION DIVISION. PROGRAM-ID. HELLO. DATA DIVISION. WORKING-STORAGE SECTION. 01 WS-NUM1 PIC S9(9) VALUE -1234. 01 WS-NUM2 PIC S9(9) VALUE 123456. PROCEDURE DIVISION. A000-FIRST-PARA. IF WS-NUM1 IS POSITIVE THEN DISPLAY ”WS-NUM1 IS POSITIVE”. IF WS-NUM1 IS NEGATIVE THEN DISPLAY ”WS-NUM1 IS NEGATIVE”. IF WS-NUM1 IS ZERO THEN DISPLAY ”WS-NUM1 IS ZERO”. IF WS-NUM2 IS POSITIVE THEN DISPLAY ”WS-NUM2 IS POSITIVE”. STOP RUN. JCL to execute the above COBOL program − //SAMPLE JOB(TESTJCL,XXXXXX),CLASS = A,MSGCLASS = C //STEP1 EXEC PGM = HELLO When you compile and execute the above program it produces the following result − WS-NUM1 IS NEGATIVE WS-NUM2 IS POSITIVE Class Condition Class condition is used to check if an operand contains only alphabets or numeric data. Spaces are considered in ALPHABETIC, ALPHABETIC-LOWER, and ALPHABETIC-UPPER. Syntax Following is the syntax of Class condition statements − [Data Name/Arithmetic Operation>] [IS] [NOT] [NUMERIC, ALPHABETIC, ALPHABETIC-LOWER, ALPHABETIC-UPPER] [Data Name/Arithmetic Operation] Example Live Demo IDENTIFICATION DIVISION. PROGRAM-ID. HELLO. DATA DIVISION. WORKING-STORAGE SECTION. 01 WS-NUM1 PIC X(9) VALUE ”ABCD ”. 01 WS-NUM2 PIC 9(9) VALUE 123456789. PROCEDURE DIVISION. A000-FIRST-PARA. IF WS-NUM1 IS ALPHABETIC THEN DISPLAY ”WS-NUM1 IS ALPHABETIC”. IF WS-NUM1 IS NUMERIC THEN DISPLAY ”WS-NUM1 IS NUMERIC”. IF WS-NUM2 IS NUMERIC THEN DISPLAY ”WS-NUM2 IS NUMERIC”. STOP RUN. JCL to execute the above COBOL program − //SAMPLE JOB(TESTJCL,XXXXXX),CLASS = A,MSGCLASS = C //STEP1 EXEC PGM = HELLO When you compile and execute the above program, it produces the following result − WS-NUM1 IS ALPHABETIC WS-NUM2 IS NUMERIC Condition-name Condition A condition-name is a user-defined name. It contains a set of values specified by the user. It behaves like Boolean variables. They are defined with level number 88. It will not have a PIC clause. Syntax Following is the syntax of user-defined condition statements − 88 [Condition-Name] VALUE [IS, ARE] [LITERAL] [THRU LITERAL]. Example Live Demo IDENTIFICATION DIVISION. PROGRAM-ID. HELLO. DATA DIVISION. WORKING-STORAGE SECTION. 01 WS-NUM PIC 9(3). 88 PASS VALUES ARE 041 THRU 100. 88 FAIL VALUES ARE 000 THRU 40. PROCEDURE DIVISION. A000-FIRST-PARA. MOVE 65 TO WS-NUM. IF PASS DISPLAY ”Passed with ” WS-NUM ” marks”. IF FAIL DISPLAY ”FAILED with ” WS-NUM ”marks”. STOP RUN. JCL to execute the above COBOL program − //SAMPLE JOB(TESTJCL,XXXXXX),CLASS = A,MSGCLASS = C //STEP1 EXEC PGM = HELLO When you compile and execute the above program, it produces the following result − Passed with 065 marks Negated Condition Negated condition is given by using the NOT keyword. If a condition