Scenario1 - Declare the cursor for retrieving all employee names from the employee_details table.

   EXEC SQL 
	DECLARE E1 CURSOR FOR
     	SELECT EMP_NAME
     	FROM   EMPLOYEE_DETAILS 
   END-EXEC.

Scenario2 - Declare the read-only cursor for retrieving all employee names from the employee_details table.

   EXEC SQL 
	DECLARE E2 CURSOR FOR
     	SELECT EMP_NAME
     	FROM   EMPLOYEE_DETAILS 
		FOR    FETCH ONLY 
   END-EXEC.

Scenario3 - Declare the read-only cursor for retrieving all employee names from highest salary to lowest.

   EXEC SQL 
	DECLARE E2 CURSOR FOR
     	SELECT EMP_NAME
     	FROM   EMPLOYEE_DETAILS 
		ORDER  BY SALARY DESC
		FOR    FETCH ONLY 
   END-EXEC.

Scenario4 -Declare the read-only cursor for retrieving the sum of salaries at the designation level.

   EXEC SQL 
	DECLARE E2 CURSOR FOR
     	SELECT DESIGNATION,
		       SUM(SALARY) SALARIES_TOTAL
     	FROM   EMPLOYEE_DETAILS 
		GROUP  BY DESIGNATION
		FOR    FETCH ONLY 
   END-EXEC.

Scenario5 - Declare the read-only cursor for retrieving the sum of salaries > 18000 at designation level.

   EXEC SQL 
	DECLARE E2 CURSOR FOR
     	SELECT DESIGNATION,
		       SUM(SALARY) SALARIES_TOTAL
     	FROM   EMPLOYEE_DETAILS 
		GROUP  BY DESIGNATION
		HAVING SUM(SALARY) > 18000
		FOR    FETCH ONLY 
   END-EXEC.

Practical Example -

Scenario - The below example describes how the read-only cursor is coded in the COBOL + DB2 program.

Requirement - Display employee_details table data.

----+----1----+----2----+----3----+----4----+----5----+
       IDENTIFICATION DIVISION. 
       PROGRAM-ID. CREADONL.

       ENVIRONMENT DIVISION.
       DATA DIVISION.
       WORKING-STORAGE SECTION.

           EXEC SQL
             INCLUDE SQLCA
           END-EXEC.
 
           EXEC SQL
             INCLUDE EMPLDET
           END-EXEC.

      * DECLARING READONLY CURSOR  
           EXEC SQL
                DECLARE CSR1 CURSOR FOR
                SELECT EMP_ID,
                       EMP_NAME,
                       DESIGNATION,
                       MANAGER_ID,
                       DATE_OF_HIRE,
                       SALARY,
                       DEPT_ID
                FROM   EMPLOYEE_DETAILS
                FOR    FETCH ONLY
           END-EXEC.

       PROCEDURE DIVISION.

      * OPENING CURSOR
           EXEC SQL 
                OPEN CSR1
           END-EXEC.

      * FETCHING CURSOR LOOP UNTIL END OF RESULT TABLE 
           IF SQLCODE EQUAL ZERO
              PERFORM FETCH-EMP-DETAILS 
                 THRU FETCH-EMP-DETAILS-EXIT
                UNTIL SQLCODE NOT EQUAL 0 
           END-IF.

      * CLOSING CURSOR 
           EXEC SQL
                CLOSE CSR1
           END-EXEC. 
           STOP RUN.

       FETCH-EMP-DETAILS.

      * FETCH CURSOR
           EXEC SQL
                FETCH CSR1
                INTO   :EMP-ID,
                       :EMP-NAME,
                       :DESIGNATION,
                       :MANAGER-ID
                       :MANAGER-ID-NI,
                       :DATE-OF-HIRE,
                       :SALARY,
                       :DEPT-ID
           END-EXEC.

           EVALUATE SQLCODE
               WHEN ZERO
                    DISPLAY  EMP-ID, "|", EMP-NAME, "|",
                             DESIGNATION, "|", MANAGER-ID, "|",
                             DATE-OF-HIRE, "|", SALARY, "|", DEPT-ID
               WHEN 100
                    CONTINUE
               WHEN OTHER
                    DISPLAY "DB2 ERROR:  ", SQLCODE
           END-EVALUATE.

       FETCH-EMP-DETAILS-EXIT.
           EXIT.

Output -

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