What are EXEC and EXECUTE statements in COBOL?

EXEC and EXECUTE statements in COBOL are used for embedded SQL processing, calling external programs, and executing system commands. EXEC SQL is commonly used for database operations, while EXECUTE can run dynamic SQL statements and system commands.

How do I use EXEC SQL in COBOL programs?

Use EXEC SQL by enclosing SQL statements within EXEC SQL and END-EXEC delimiters. Include SQLCA for communication, declare host variables for data exchange, and handle SQL return codes. The preprocessor converts these statements into appropriate database calls.

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COBOL Tutorial

COBOL EXEC and EXECUTE Statements

The EXEC and EXECUTE statements represent powerful integration mechanisms in COBOL programming, providing sophisticated capabilities for embedded SQL processing, database interaction, external program execution, and system command invocation. These statements serve as bridges between COBOL applications and external systems, enabling seamless data access, dynamic SQL execution, and comprehensive system integration while maintaining the structured programming paradigm inherent in COBOL development environments.

Comprehensive EXEC SQL Implementation

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IDENTIFICATION DIVISION.
PROGRAM-ID. EXEC-SQL-COMPREHENSIVE.
 
DATA DIVISION.
WORKING-STORAGE SECTION.
*> SQL Communication Area
EXEC SQL
    INCLUDE SQLCA
END-EXEC.
 
*> Host Variables for Database Operations
01  HOST-VARIABLES.
    05  HV-EMPLOYEE-ID          PIC 9(6).
    05  HV-EMPLOYEE-NAME        PIC X(30).
    05  HV-EMPLOYEE-SALARY      PIC 9(7)V99.
    05  HV-DEPARTMENT-CODE      PIC X(4).
    05  HV-HIRE-DATE            PIC X(10).
    05  HV-EMPLOYEE-COUNT       PIC 9(5).
    05  HV-AVERAGE-SALARY       PIC 9(7)V99.
    05  HV-MAX-SALARY           PIC 9(7)V99.
    05  HV-MIN-SALARY           PIC 9(7)V99.
 
*> Dynamic SQL Variables
01  DYNAMIC-SQL-VARIABLES.
    05  SQL-STATEMENT           PIC X(500).
    05  SQL-STATEMENT-LENGTH    PIC 9(4).
    05  SQL-CURSOR-NAME         PIC X(18) VALUE 'DYNAMIC_CURSOR'.
    05  SQL-PREPARE-NAME        PIC X(18) VALUE 'DYNAMIC_STMT'.
 
*> SQL Status and Error Handling
01  SQL-STATUS-HANDLING.
    05  SQL-OPERATION           PIC X(20).
    05  SQL-RETURN-CODE         PIC S9(9) COMP.
    05  SQL-ERROR-MESSAGE       PIC X(100).
    05  SQL-ROWS-PROCESSED      PIC 9(7).
    05  SQL-WARNING-FLAG        PIC X VALUE 'N'.
        88  SQL-WARNING         VALUE 'Y'.
        88  NO-SQL-WARNING      VALUE 'N'.
 
*> Transaction Control Variables
01  TRANSACTION-CONTROL.
    05  TRANSACTION-STATUS      PIC X VALUE 'N'.
        88  TRANSACTION-ACTIVE  VALUE 'Y'.
        88  NO-TRANSACTION      VALUE 'N'.
    05  SAVEPOINT-NAME          PIC X(20).
    05  COMMIT-COUNT            PIC 9(5) VALUE 0.
    05  ROLLBACK-COUNT          PIC 9(5) VALUE 0.
 
*> Performance Monitoring
01  PERFORMANCE-METRICS.
    05  TOTAL-SQL-OPERATIONS    PIC 9(7) VALUE 0.
    05  SUCCESSFUL-OPERATIONS   PIC 9(7) VALUE 0.
    05  FAILED-OPERATIONS       PIC 9(7) VALUE 0.
    05  SELECT-OPERATIONS       PIC 9(5) VALUE 0.
    05  INSERT-OPERATIONS       PIC 9(5) VALUE 0.
    05  UPDATE-OPERATIONS       PIC 9(5) VALUE 0.
    05  DELETE-OPERATIONS       PIC 9(5) VALUE 0.
 
PROCEDURE DIVISION.
MAIN-PROCESSING.
    PERFORM INITIALIZE-DATABASE-CONNECTION
    PERFORM DEMONSTRATE-BASIC-SQL-OPERATIONS
    PERFORM DEMONSTRATE-CURSOR-OPERATIONS
    PERFORM DEMONSTRATE-DYNAMIC-SQL
    PERFORM DEMONSTRATE-TRANSACTION-CONTROL
    PERFORM DEMONSTRATE-STORED-PROCEDURES
    PERFORM DISPLAY-PERFORMANCE-METRICS
    PERFORM CLEANUP-DATABASE-CONNECTION
    STOP RUN.
 
INITIALIZE-DATABASE-CONNECTION.
    DISPLAY 'Initializing database connection...'
    
    EXEC SQL
        CONNECT TO :DATABASE-NAME
        USER :USER-ID
        USING :PASSWORD
    END-EXEC
    
    MOVE 'CONNECT' TO SQL-OPERATION
    PERFORM CHECK-SQL-STATUS
    
    IF SQLCODE = 0
        DISPLAY 'Database connection established successfully'
        SET TRANSACTION-ACTIVE TO TRUE
    ELSE
        DISPLAY 'Database connection failed'
        PERFORM DISPLAY-SQL-ERROR
        STOP RUN
    END-IF.
 
DEMONSTRATE-BASIC-SQL-OPERATIONS.
    DISPLAY 'Demonstrating basic SQL operations...'
    
    PERFORM INSERT-EMPLOYEE-RECORD
    PERFORM SELECT-EMPLOYEE-RECORD
    PERFORM UPDATE-EMPLOYEE-RECORD
    PERFORM DELETE-EMPLOYEE-RECORD
    PERFORM AGGREGATE-OPERATIONS.
 
INSERT-EMPLOYEE-RECORD.
    DISPLAY 'Inserting employee record...'
    
    MOVE 123456 TO HV-EMPLOYEE-ID
    MOVE 'JOHN SMITH' TO HV-EMPLOYEE-NAME
    MOVE 75000.00 TO HV-EMPLOYEE-SALARY
    MOVE 'IT01' TO HV-DEPARTMENT-CODE
    MOVE '2024-01-15' TO HV-HIRE-DATE
    
    EXEC SQL
        INSERT INTO EMPLOYEES
        (EMPLOYEE_ID, EMPLOYEE_NAME, SALARY, DEPARTMENT_CODE, HIRE_DATE)
        VALUES
        (:HV-EMPLOYEE-ID, :HV-EMPLOYEE-NAME, :HV-EMPLOYEE-SALARY,
         :HV-DEPARTMENT-CODE, :HV-HIRE-DATE)
    END-EXEC
    
    MOVE 'INSERT' TO SQL-OPERATION
    ADD 1 TO INSERT-OPERATIONS
    PERFORM CHECK-SQL-STATUS
    
    IF SQLCODE = 0
        DISPLAY 'Employee record inserted successfully'
        ADD 1 TO SUCCESSFUL-OPERATIONS
    ELSE
        DISPLAY 'Insert operation failed'
        ADD 1 TO FAILED-OPERATIONS
        PERFORM DISPLAY-SQL-ERROR
    END-IF.
 
SELECT-EMPLOYEE-RECORD.
    DISPLAY 'Selecting employee record...'
    
    MOVE 123456 TO HV-EMPLOYEE-ID
    
    EXEC SQL
        SELECT EMPLOYEE_NAME, SALARY, DEPARTMENT_CODE, HIRE_DATE
        INTO :HV-EMPLOYEE-NAME, :HV-EMPLOYEE-SALARY,
             :HV-DEPARTMENT-CODE, :HV-HIRE-DATE
        FROM EMPLOYEES
        WHERE EMPLOYEE_ID = :HV-EMPLOYEE-ID
    END-EXEC
    
    MOVE 'SELECT' TO SQL-OPERATION
    ADD 1 TO SELECT-OPERATIONS
    PERFORM CHECK-SQL-STATUS
    
    EVALUATE SQLCODE
        WHEN 0
            DISPLAY 'Employee record found:'
            DISPLAY 'Name: ' HV-EMPLOYEE-NAME
            DISPLAY 'Salary: ' HV-EMPLOYEE-SALARY
            DISPLAY 'Department: ' HV-DEPARTMENT-CODE
            DISPLAY 'Hire Date: ' HV-HIRE-DATE
            ADD 1 TO SUCCESSFUL-OPERATIONS
        WHEN 100
            DISPLAY 'No employee found with ID: ' HV-EMPLOYEE-ID
            ADD 1 TO SUCCESSFUL-OPERATIONS
        WHEN OTHER
            DISPLAY 'Select operation failed'
            ADD 1 TO FAILED-OPERATIONS
            PERFORM DISPLAY-SQL-ERROR
    END-EVALUATE.
 
UPDATE-EMPLOYEE-RECORD.
    DISPLAY 'Updating employee record...'
    
    MOVE 123456 TO HV-EMPLOYEE-ID
    MOVE 80000.00 TO HV-EMPLOYEE-SALARY
    
    EXEC SQL
        UPDATE EMPLOYEES
        SET SALARY = :HV-EMPLOYEE-SALARY
        WHERE EMPLOYEE_ID = :HV-EMPLOYEE-ID
    END-EXEC
    
    MOVE 'UPDATE' TO SQL-OPERATION
    ADD 1 TO UPDATE-OPERATIONS
    PERFORM CHECK-SQL-STATUS
    
    IF SQLCODE = 0
        DISPLAY 'Employee salary updated successfully'
        DISPLAY 'Rows affected: ' SQLERRD(3)
        ADD 1 TO SUCCESSFUL-OPERATIONS
    ELSE
        DISPLAY 'Update operation failed'
        ADD 1 TO FAILED-OPERATIONS
        PERFORM DISPLAY-SQL-ERROR
    END-IF.
 
DELETE-EMPLOYEE-RECORD.
    DISPLAY 'Deleting employee record...'
    
    MOVE 123456 TO HV-EMPLOYEE-ID
    
    EXEC SQL
        DELETE FROM EMPLOYEES
        WHERE EMPLOYEE_ID = :HV-EMPLOYEE-ID
    END-EXEC
    
    MOVE 'DELETE' TO SQL-OPERATION
    ADD 1 TO DELETE-OPERATIONS
    PERFORM CHECK-SQL-STATUS
    
    IF SQLCODE = 0
        DISPLAY 'Employee record deleted successfully'
        DISPLAY 'Rows affected: ' SQLERRD(3)
        ADD 1 TO SUCCESSFUL-OPERATIONS
    ELSE
        DISPLAY 'Delete operation failed'
        ADD 1 TO FAILED-OPERATIONS
        PERFORM DISPLAY-SQL-ERROR
    END-IF.
 
AGGREGATE-OPERATIONS.
    DISPLAY 'Performing aggregate operations...'
    
    EXEC SQL
        SELECT COUNT(*), AVG(SALARY), MAX(SALARY), MIN(SALARY)
        INTO :HV-EMPLOYEE-COUNT, :HV-AVERAGE-SALARY,
             :HV-MAX-SALARY, :HV-MIN-SALARY
        FROM EMPLOYEES
        WHERE DEPARTMENT_CODE = :HV-DEPARTMENT-CODE
    END-EXEC
    
    MOVE 'AGGREGATE' TO SQL-OPERATION
    ADD 1 TO SELECT-OPERATIONS
    PERFORM CHECK-SQL-STATUS
    
    IF SQLCODE = 0
        DISPLAY 'Aggregate results for department ' HV-DEPARTMENT-CODE ':'
        DISPLAY 'Employee count: ' HV-EMPLOYEE-COUNT
        DISPLAY 'Average salary: ' HV-AVERAGE-SALARY
        DISPLAY 'Maximum salary: ' HV-MAX-SALARY
        DISPLAY 'Minimum salary: ' HV-MIN-SALARY
        ADD 1 TO SUCCESSFUL-OPERATIONS
    ELSE
        DISPLAY 'Aggregate operation failed'
        ADD 1 TO FAILED-OPERATIONS
        PERFORM DISPLAY-SQL-ERROR
    END-IF.
 
DEMONSTRATE-CURSOR-OPERATIONS.
    DISPLAY 'Demonstrating cursor operations...'
    
    EXEC SQL
        DECLARE EMP_CURSOR CURSOR FOR
        SELECT EMPLOYEE_ID, EMPLOYEE_NAME, SALARY
        FROM EMPLOYEES
        WHERE DEPARTMENT_CODE = :HV-DEPARTMENT-CODE
        ORDER BY SALARY DESC
    END-EXEC
    
    EXEC SQL
        OPEN EMP_CURSOR
    END-EXEC
    
    MOVE 'CURSOR OPEN' TO SQL-OPERATION
    PERFORM CHECK-SQL-STATUS
    
    IF SQLCODE = 0
        DISPLAY 'Cursor opened successfully'
        PERFORM FETCH-CURSOR-RECORDS
        PERFORM CLOSE-CURSOR
    ELSE
        DISPLAY 'Cursor open failed'
        PERFORM DISPLAY-SQL-ERROR
    END-IF.
 
FETCH-CURSOR-RECORDS.
    DISPLAY 'Fetching cursor records...'
    
    PERFORM UNTIL SQLCODE NOT = 0
        EXEC SQL
            FETCH EMP_CURSOR
            INTO :HV-EMPLOYEE-ID, :HV-EMPLOYEE-NAME, :HV-EMPLOYEE-SALARY
        END-EXEC
        
        MOVE 'CURSOR FETCH' TO SQL-OPERATION
        PERFORM CHECK-SQL-STATUS
        
        EVALUATE SQLCODE
            WHEN 0
                DISPLAY 'Employee: ' HV-EMPLOYEE-ID ' ' 
                        HV-EMPLOYEE-NAME ' ' HV-EMPLOYEE-SALARY
                ADD 1 TO SUCCESSFUL-OPERATIONS
            WHEN 100
                DISPLAY 'End of cursor reached'
            WHEN OTHER
                DISPLAY 'Cursor fetch failed'
                ADD 1 TO FAILED-OPERATIONS
                PERFORM DISPLAY-SQL-ERROR
        END-EVALUATE
    END-PERFORM.
 
CLOSE-CURSOR.
    EXEC SQL
        CLOSE EMP_CURSOR
    END-EXEC
    
    MOVE 'CURSOR CLOSE' TO SQL-OPERATION
    PERFORM CHECK-SQL-STATUS
    
    IF SQLCODE = 0
        DISPLAY 'Cursor closed successfully'
    ELSE
        DISPLAY 'Cursor close failed'
        PERFORM DISPLAY-SQL-ERROR
    END-IF.
 
DEMONSTRATE-DYNAMIC-SQL.
    DISPLAY 'Demonstrating dynamic SQL...'
    
    MOVE 'SELECT COUNT(*) FROM EMPLOYEES WHERE SALARY > ?' 
         TO SQL-STATEMENT
    MOVE LENGTH OF SQL-STATEMENT TO SQL-STATEMENT-LENGTH
    
    EXEC SQL
        PREPARE :SQL-PREPARE-NAME FROM :SQL-STATEMENT
    END-EXEC
    
    MOVE 'PREPARE' TO SQL-OPERATION
    PERFORM CHECK-SQL-STATUS
    
    IF SQLCODE = 0
        DISPLAY 'Dynamic SQL prepared successfully'
        PERFORM EXECUTE-DYNAMIC-SQL
    ELSE
        DISPLAY 'Dynamic SQL prepare failed'
        PERFORM DISPLAY-SQL-ERROR
    END-IF.
 
EXECUTE-DYNAMIC-SQL.
    MOVE 50000.00 TO HV-EMPLOYEE-SALARY
    
    EXEC SQL
        EXECUTE :SQL-PREPARE-NAME
        USING :HV-EMPLOYEE-SALARY
        INTO :HV-EMPLOYEE-COUNT
    END-EXEC
    
    MOVE 'EXECUTE' TO SQL-OPERATION
    PERFORM CHECK-SQL-STATUS
    
    IF SQLCODE = 0
        DISPLAY 'Dynamic SQL executed successfully'
        DISPLAY 'Employees with salary > ' HV-EMPLOYEE-SALARY 
                ': ' HV-EMPLOYEE-COUNT
        ADD 1 TO SUCCESSFUL-OPERATIONS
    ELSE
        DISPLAY 'Dynamic SQL execution failed'
        ADD 1 TO FAILED-OPERATIONS
        PERFORM DISPLAY-SQL-ERROR
    END-IF.
 
DEMONSTRATE-TRANSACTION-CONTROL.
    DISPLAY 'Demonstrating transaction control...'
    
    EXEC SQL
        BEGIN TRANSACTION
    END-EXEC
    
    MOVE 'BEGIN TRANSACTION' TO SQL-OPERATION
    PERFORM CHECK-SQL-STATUS
    
    IF SQLCODE = 0
        DISPLAY 'Transaction started successfully'
        PERFORM TRANSACTION-OPERATIONS
    ELSE
        DISPLAY 'Transaction start failed'
        PERFORM DISPLAY-SQL-ERROR
    END-IF.
 
TRANSACTION-OPERATIONS.
    *> Perform multiple operations in transaction
    MOVE 'TRANS_SAVE_1' TO SAVEPOINT-NAME
    
    EXEC SQL
        SAVEPOINT :SAVEPOINT-NAME
    END-EXEC
    
    MOVE 'SAVEPOINT' TO SQL-OPERATION
    PERFORM CHECK-SQL-STATUS
    
    *> Simulate transaction success
    EXEC SQL
        COMMIT
    END-EXEC
    
    MOVE 'COMMIT' TO SQL-OPERATION
    PERFORM CHECK-SQL-STATUS
    
    IF SQLCODE = 0
        DISPLAY 'Transaction committed successfully'
        ADD 1 TO COMMIT-COUNT
    ELSE
        DISPLAY 'Transaction commit failed'
        PERFORM ROLLBACK-TRANSACTION
    END-IF.
 
ROLLBACK-TRANSACTION.
    EXEC SQL
        ROLLBACK
    END-EXEC
    
    MOVE 'ROLLBACK' TO SQL-OPERATION
    PERFORM CHECK-SQL-STATUS
    
    IF SQLCODE = 0
        DISPLAY 'Transaction rolled back successfully'
        ADD 1 TO ROLLBACK-COUNT
    ELSE
        DISPLAY 'Transaction rollback failed'
        PERFORM DISPLAY-SQL-ERROR
    END-IF.
 
DEMONSTRATE-STORED-PROCEDURES.
    DISPLAY 'Demonstrating stored procedure calls...'
    
    MOVE 'IT01' TO HV-DEPARTMENT-CODE
    
    EXEC SQL
        CALL GET_DEPT_STATISTICS(:HV-DEPARTMENT-CODE,
                                 :HV-EMPLOYEE-COUNT,
                                 :HV-AVERAGE-SALARY)
    END-EXEC
    
    MOVE 'STORED PROCEDURE' TO SQL-OPERATION
    PERFORM CHECK-SQL-STATUS
    
    IF SQLCODE = 0
        DISPLAY 'Stored procedure executed successfully'
        DISPLAY 'Department statistics:'
        DISPLAY 'Employee count: ' HV-EMPLOYEE-COUNT
        DISPLAY 'Average salary: ' HV-AVERAGE-SALARY
        ADD 1 TO SUCCESSFUL-OPERATIONS
    ELSE
        DISPLAY 'Stored procedure call failed'
        ADD 1 TO FAILED-OPERATIONS
        PERFORM DISPLAY-SQL-ERROR
    END-IF.
 
CHECK-SQL-STATUS.
    ADD 1 TO TOTAL-SQL-OPERATIONS
    MOVE SQLCODE TO SQL-RETURN-CODE
    
    EVALUATE SQLCODE
        WHEN 0
            SET NO-SQL-WARNING TO TRUE
        WHEN POSITIVE
            SET SQL-WARNING TO TRUE
            DISPLAY 'SQL Warning for ' SQL-OPERATION ': ' SQLCODE
        WHEN NEGATIVE
            DISPLAY 'SQL Error for ' SQL-OPERATION ': ' SQLCODE
    END-EVALUATE.
 
DISPLAY-SQL-ERROR.
    DISPLAY 'SQL Error Details:'
    DISPLAY 'Operation: ' SQL-OPERATION
    DISPLAY 'SQLCODE: ' SQLCODE
    DISPLAY 'SQLERRM: ' SQLERRM
    DISPLAY 'SQLERRD(3): ' SQLERRD(3).
 
DISPLAY-PERFORMANCE-METRICS.
    DISPLAY 'SQL Performance Metrics:'
    DISPLAY '========================'
    DISPLAY 'Total operations: ' TOTAL-SQL-OPERATIONS
    DISPLAY 'Successful operations: ' SUCCESSFUL-OPERATIONS
    DISPLAY 'Failed operations: ' FAILED-OPERATIONS
    DISPLAY 'SELECT operations: ' SELECT-OPERATIONS
    DISPLAY 'INSERT operations: ' INSERT-OPERATIONS
    DISPLAY 'UPDATE operations: ' UPDATE-OPERATIONS
    DISPLAY 'DELETE operations: ' DELETE-OPERATIONS
    DISPLAY 'Commits: ' COMMIT-COUNT
    DISPLAY 'Rollbacks: ' ROLLBACK-COUNT
    
    IF TOTAL-SQL-OPERATIONS > 0
        COMPUTE SUCCESSFUL-OPERATIONS = 
            (SUCCESSFUL-OPERATIONS / TOTAL-SQL-OPERATIONS) * 100
        DISPLAY 'Success rate: ' SUCCESSFUL-OPERATIONS '%'
    END-IF.
 
CLEANUP-DATABASE-CONNECTION.
    DISPLAY 'Cleaning up database connection...'
    
    EXEC SQL
        DISCONNECT
    END-EXEC
    
    MOVE 'DISCONNECT' TO SQL-OPERATION
    PERFORM CHECK-SQL-STATUS
    
    IF SQLCODE = 0
        DISPLAY 'Database disconnected successfully'
    ELSE
        DISPLAY 'Database disconnect failed'
        PERFORM DISPLAY-SQL-ERROR
    END-IF.

EXECUTE Statement for Dynamic Operations

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IDENTIFICATION DIVISION.
PROGRAM-ID. EXECUTE-DYNAMIC-OPERATIONS.
 
DATA DIVISION.
WORKING-STORAGE SECTION.
01  DYNAMIC-EXECUTION-CONTROL.
    05  COMMAND-STRING          PIC X(200).
    05  COMMAND-LENGTH          PIC 9(4).
    05  EXECUTION-STATUS        PIC X VALUE 'N'.
        88  EXECUTION-SUCCESS   VALUE 'Y'.
        88  EXECUTION-FAILED    VALUE 'N'.
    05  RETURN-CODE             PIC 9(4).
    05  OUTPUT-BUFFER           PIC X(500).
    05  ERROR-BUFFER            PIC X(200).
 
01  SYSTEM-INTEGRATION.
    05  SYSTEM-COMMAND          PIC X(100).
    05  PARAMETER-LIST          PIC X(200).
    05  ENVIRONMENT-VARIABLE    PIC X(50).
    05  ENVIRONMENT-VALUE       PIC X(100).
    05  PROCESS-ID              PIC 9(8).
    05  EXECUTION-TIME          PIC 9(6).
 
PROCEDURE DIVISION.
MAIN-PROCESSING.
    PERFORM DEMONSTRATE-EXECUTE-IMMEDIATE
    PERFORM DEMONSTRATE-SYSTEM-COMMANDS
    PERFORM DEMONSTRATE-PROGRAM-EXECUTION
    STOP RUN.
 
DEMONSTRATE-EXECUTE-IMMEDIATE.
    DISPLAY 'Demonstrating EXECUTE IMMEDIATE...'
    
    MOVE 'CREATE TABLE TEMP_TABLE (ID INT, NAME VARCHAR(50))' 
         TO COMMAND-STRING
    
    EXEC SQL
        EXECUTE IMMEDIATE :COMMAND-STRING
    END-EXEC
    
    IF SQLCODE = 0
        DISPLAY 'Table created successfully via EXECUTE IMMEDIATE'
        SET EXECUTION-SUCCESS TO TRUE
    ELSE
        DISPLAY 'Table creation failed'
        SET EXECUTION-FAILED TO TRUE
    END-IF.
 
DEMONSTRATE-SYSTEM-COMMANDS.
    DISPLAY 'Demonstrating system command execution...'
    
    MOVE 'DIR C:TEMP' TO SYSTEM-COMMAND
    
    *> Platform-specific execution
    CALL 'SYSTEM' USING SYSTEM-COMMAND
        RETURNING RETURN-CODE
    
    IF RETURN-CODE = 0
        DISPLAY 'System command executed successfully'
        SET EXECUTION-SUCCESS TO TRUE
    ELSE
        DISPLAY 'System command failed with code: ' RETURN-CODE
        SET EXECUTION-FAILED TO TRUE
    END-IF.
 
DEMONSTRATE-PROGRAM-EXECUTION.
    DISPLAY 'Demonstrating program execution...'
    
    MOVE 'BATCH-PROCESSOR' TO COMMAND-STRING
    MOVE 'INPUT=DATA.TXT OUTPUT=RESULT.TXT' TO PARAMETER-LIST
    
    CALL COMMAND-STRING USING PARAMETER-LIST
        RETURNING RETURN-CODE
    
    IF RETURN-CODE = 0
        DISPLAY 'Program executed successfully'
        SET EXECUTION-SUCCESS TO TRUE
    ELSE
        DISPLAY 'Program execution failed'
        SET EXECUTION-FAILED TO TRUE
    END-IF.

Best Practices and FAQ

EXEC SQL Best Practices

• Always include SQLCA for error handling
• Use host variables for data exchange
• Check SQLCODE after every operation
• Implement proper transaction control
• Use cursors for multi-row processing

Dynamic SQL Guidelines

• Validate input parameters thoroughly
• Use prepared statements for performance
• Implement SQL injection prevention
• Handle variable-length statements
• Monitor execution performance

COBOL Tutorial

COBOL EXEC and EXECUTE Statements

Comprehensive EXEC SQL Implementation

EXECUTE Statement for Dynamic Operations

Best Practices and FAQ

What's the difference between EXEC SQL and EXECUTE?

How do I handle SQL errors in EXEC SQL statements?

What are the security considerations for EXECUTE statements?