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COBOL Tutorial

COBOL FD Statement

The FD (File Description) statement represents a fundamental component of COBOL file processing architecture, serving as the primary mechanism for defining file characteristics, record structures, and processing attributes within the File Section of the Data Division. This statement embodies the principles of structured data organization by providing comprehensive file metadata specification, enabling sophisticated file processing capabilities, and supporting various file organizations including sequential, indexed, and relative access methods while maintaining data integrity and processing efficiency through detailed file attribute definition.

Comprehensive FD Statement Implementation

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IDENTIFICATION DIVISION. PROGRAM-ID. FD-COMPREHENSIVE-DEMONSTRATION. ENVIRONMENT DIVISION. INPUT-OUTPUT SECTION. FILE-CONTROL. SELECT CUSTOMER-MASTER-FILE ASSIGN TO 'CUSTMAST.DAT' ORGANIZATION IS SEQUENTIAL ACCESS MODE IS SEQUENTIAL FILE STATUS IS CUSTOMER-FILE-STATUS. SELECT TRANSACTION-FILE ASSIGN TO 'TRANSACT.DAT' ORGANIZATION IS SEQUENTIAL ACCESS MODE IS SEQUENTIAL FILE STATUS IS TRANSACTION-FILE-STATUS. SELECT REPORT-FILE ASSIGN TO 'REPORT.RPT' ORGANIZATION IS SEQUENTIAL ACCESS MODE IS SEQUENTIAL FILE STATUS IS REPORT-FILE-STATUS. SELECT INDEXED-CUSTOMER-FILE ASSIGN TO 'CUSTINDX.DAT' ORGANIZATION IS INDEXED ACCESS MODE IS DYNAMIC RECORD KEY IS IDX-CUSTOMER-ID FILE STATUS IS INDEXED-FILE-STATUS. SELECT ERROR-LOG-FILE ASSIGN TO 'ERRORS.LOG' ORGANIZATION IS SEQUENTIAL ACCESS MODE IS SEQUENTIAL FILE STATUS IS ERROR-LOG-STATUS. DATA DIVISION. FILE SECTION. *> Sequential Customer Master File with comprehensive FD FD CUSTOMER-MASTER-FILE BLOCK CONTAINS 0 RECORDS RECORD CONTAINS 200 CHARACTERS LABEL RECORDS ARE STANDARD DATA RECORDS ARE CUSTOMER-MASTER-RECORD. 01 CUSTOMER-MASTER-RECORD. 05 CM-CUSTOMER-ID PIC 9(8). 05 CM-CUSTOMER-NAME PIC X(30). 05 CM-ADDRESS-LINE-1 PIC X(25). 05 CM-ADDRESS-LINE-2 PIC X(25). 05 CM-CITY PIC X(20). 05 CM-STATE PIC X(2). 05 CM-ZIP-CODE PIC X(10). 05 CM-PHONE-NUMBER PIC X(15). 05 CM-EMAIL-ADDRESS PIC X(50). 05 CM-ACCOUNT-BALANCE PIC 9(9)V99. 05 CM-CREDIT-LIMIT PIC 9(9)V99. 05 CM-LAST-PAYMENT-DATE PIC 9(8). 05 CM-ACCOUNT-STATUS PIC X(10). 05 CM-CUSTOMER-TYPE PIC X(10). 05 CM-DATE-OPENED PIC 9(8). 05 CM-LAST-ACTIVITY-DATE PIC 9(8). 05 FILLER PIC X(3). *> Transaction File with variable record formats FD TRANSACTION-FILE BLOCK CONTAINS 0 RECORDS RECORD CONTAINS 150 TO 300 CHARACTERS DEPENDING ON TRANS-RECORD-LENGTH LABEL RECORDS ARE STANDARD DATA RECORDS ARE TRANSACTION-RECORD. 01 TRANSACTION-RECORD. 05 TR-RECORD-TYPE PIC X(2). 88 DEPOSIT-RECORD VALUE 'DP'. 88 WITHDRAWAL-RECORD VALUE 'WD'. 88 TRANSFER-RECORD VALUE 'TR'. 88 PAYMENT-RECORD VALUE 'PM'. 88 INQUIRY-RECORD VALUE 'IN'. 05 TR-TRANSACTION-ID PIC 9(10). 05 TR-CUSTOMER-ID PIC 9(8). 05 TR-TRANSACTION-DATE PIC 9(8). 05 TR-TRANSACTION-TIME PIC 9(6). 05 TR-AMOUNT PIC 9(9)V99. 05 TR-DESCRIPTION PIC X(50). 05 TR-PROCESSING-CODE PIC X(4). 05 TR-AUTHORIZATION-CODE PIC X(8). 05 TR-BRANCH-CODE PIC X(6). 05 TR-TELLER-ID PIC X(8). 05 TR-VARIABLE-DATA PIC X(150). 05 TR-RECORD-LENGTH PIC 9(3). *> Report File with fixed format FD REPORT-FILE BLOCK CONTAINS 0 RECORDS RECORD CONTAINS 132 CHARACTERS LABEL RECORDS ARE OMITTED DATA RECORDS ARE REPORT-HEADER-RECORD REPORT-DETAIL-RECORD REPORT-SUMMARY-RECORD. 01 REPORT-HEADER-RECORD. 05 RH-REPORT-TITLE PIC X(50). 05 RH-REPORT-DATE PIC X(10). 05 RH-PAGE-NUMBER PIC ZZ9. 05 FILLER PIC X(69). 01 REPORT-DETAIL-RECORD. 05 RD-CUSTOMER-ID PIC 9(8). 05 FILLER PIC X(2). 05 RD-CUSTOMER-NAME PIC X(30). 05 FILLER PIC X(2). 05 RD-ACCOUNT-BALANCE PIC ZZZ,ZZZ,ZZ9.99. 05 FILLER PIC X(2). 05 RD-ACCOUNT-STATUS PIC X(10). 05 FILLER PIC X(2). 05 RD-LAST-ACTIVITY PIC X(10). 05 FILLER PIC X(63). 01 REPORT-SUMMARY-RECORD. 05 RS-SUMMARY-LABEL PIC X(20). 05 FILLER PIC X(5). 05 RS-TOTAL-CUSTOMERS PIC ZZZ,ZZ9. 05 FILLER PIC X(5). 05 RS-TOTAL-BALANCE PIC ZZZ,ZZZ,ZZ9.99. 05 FILLER PIC X(5). 05 RS-AVERAGE-BALANCE PIC ZZZ,ZZ9.99. 05 FILLER PIC X(75). *> Indexed Customer File with key structure FD INDEXED-CUSTOMER-FILE BLOCK CONTAINS 0 RECORDS RECORD CONTAINS 250 CHARACTERS LABEL RECORDS ARE STANDARD DATA RECORDS ARE INDEXED-CUSTOMER-RECORD. 01 INDEXED-CUSTOMER-RECORD. 05 IDX-CUSTOMER-ID PIC 9(8). 05 IDX-CUSTOMER-DATA. 10 IDX-NAME PIC X(30). 10 IDX-ADDRESS PIC X(75). 10 IDX-PHONE PIC X(15). 10 IDX-EMAIL PIC X(50). 10 IDX-ACCOUNT-INFO. 15 IDX-BALANCE PIC 9(9)V99. 15 IDX-CREDIT-LIMIT PIC 9(9)V99. 15 IDX-STATUS PIC X(10). 15 IDX-TYPE PIC X(10). 10 IDX-DATES. 15 IDX-OPENED-DATE PIC 9(8). 15 IDX-LAST-PAYMENT PIC 9(8). 15 IDX-LAST-ACTIVITY PIC 9(8). 10 IDX-STATISTICS. 15 IDX-PAYMENT-COUNT PIC 9(5). 15 IDX-TRANSACTION-COUNT PIC 9(7). 15 IDX-INQUIRY-COUNT PIC 9(5). 10 FILLER PIC X(25). *> Error Log File with timestamp and severity FD ERROR-LOG-FILE BLOCK CONTAINS 0 RECORDS RECORD CONTAINS 200 CHARACTERS LABEL RECORDS ARE STANDARD DATA RECORDS ARE ERROR-LOG-RECORD. 01 ERROR-LOG-RECORD. 05 EL-TIMESTAMP PIC X(14). 05 EL-SEVERITY PIC X(8). 88 EL-INFO VALUE 'INFO'. 88 EL-WARNING VALUE 'WARNING'. 88 EL-ERROR VALUE 'ERROR'. 88 EL-CRITICAL VALUE 'CRITICAL'. 05 EL-PROGRAM-NAME PIC X(8). 05 EL-MODULE-NAME PIC X(20). 05 EL-ERROR-CODE PIC 9(6). 05 EL-ERROR-MESSAGE PIC X(100). 05 EL-ADDITIONAL-DATA PIC X(40). 05 FILLER PIC X(4). WORKING-STORAGE SECTION. 01 FILE-STATUS-CODES. 05 CUSTOMER-FILE-STATUS PIC XX. 88 CUSTOMER-SUCCESS VALUE '00'. 88 CUSTOMER-EOF VALUE '10'. 88 CUSTOMER-NOT-FOUND VALUE '23'. 05 TRANSACTION-FILE-STATUS PIC XX. 88 TRANS-SUCCESS VALUE '00'. 88 TRANS-EOF VALUE '10'. 88 TRANS-INVALID VALUE '24'. 05 REPORT-FILE-STATUS PIC XX. 88 REPORT-SUCCESS VALUE '00'. 88 REPORT-EOF VALUE '10'. 05 INDEXED-FILE-STATUS PIC XX. 88 INDEXED-SUCCESS VALUE '00'. 88 INDEXED-EOF VALUE '10'. 88 INDEXED-NOT-FOUND VALUE '23'. 05 ERROR-LOG-STATUS PIC XX. 88 ERROR-LOG-SUCCESS VALUE '00'. 88 ERROR-LOG-EOF VALUE '10'. 01 FD-PROCESSING-CONTROL. 05 RECORDS-READ PIC 9(7) VALUE 0. 05 RECORDS-WRITTEN PIC 9(7) VALUE 0. 05 RECORDS-PROCESSED PIC 9(7) VALUE 0. 05 ERROR-COUNT PIC 9(5) VALUE 0. 05 CURRENT-OPERATION PIC X(20). 05 TRANS-RECORD-LENGTH PIC 9(3) VALUE 150. 01 PROCESSING-TOTALS. 05 TOTAL-CUSTOMERS PIC 9(6) VALUE 0. 05 TOTAL-BALANCE PIC 9(12)V99 VALUE 0. 05 TOTAL-TRANSACTIONS PIC 9(8) VALUE 0. 05 TOTAL-DEPOSITS PIC 9(10)V99 VALUE 0. 05 TOTAL-WITHDRAWALS PIC 9(10)V99 VALUE 0. 05 AVERAGE-BALANCE PIC 9(9)V99 VALUE 0. 01 REPORT-CONTROL. 05 PAGE-NUMBER PIC 9(3) VALUE 1. 05 LINES-PER-PAGE PIC 9(2) VALUE 60. 05 CURRENT-LINE PIC 9(2) VALUE 0. 05 REPORT-DATE PIC X(10). PROCEDURE DIVISION. MAIN-PROCESSING. PERFORM INITIALIZE-FD-PROCESSING PERFORM DEMONSTRATE-SEQUENTIAL-FD PERFORM DEMONSTRATE-VARIABLE-RECORD-FD PERFORM DEMONSTRATE-REPORT-FD PERFORM DEMONSTRATE-INDEXED-FD PERFORM DEMONSTRATE-ERROR-LOG-FD PERFORM DISPLAY-FD-STATISTICS STOP RUN. INITIALIZE-FD-PROCESSING. DISPLAY 'Initializing FD processing demonstration...' MOVE 'INITIALIZATION' TO CURRENT-OPERATION MOVE FUNCTION CURRENT-DATE(1:8) TO REPORT-DATE DISPLAY 'FD processing initialization completed' DISPLAY 'Report Date: ' REPORT-DATE. DEMONSTRATE-SEQUENTIAL-FD. DISPLAY 'Demonstrating sequential FD processing...' MOVE 'SEQUENTIAL-READ' TO CURRENT-OPERATION OPEN INPUT CUSTOMER-MASTER-FILE IF CUSTOMER-SUCCESS DISPLAY 'Customer master file opened successfully' PERFORM READ-CUSTOMER-RECORDS CLOSE CUSTOMER-MASTER-FILE ELSE DISPLAY 'Failed to open customer master file' DISPLAY 'Status: ' CUSTOMER-FILE-STATUS ADD 1 TO ERROR-COUNT END-IF. READ-CUSTOMER-RECORDS. DISPLAY 'Reading customer records with FD structure...' PERFORM UNTIL CUSTOMER-EOF READ CUSTOMER-MASTER-FILE AT END DISPLAY 'End of customer file reached' NOT AT END PERFORM PROCESS-CUSTOMER-RECORD END-READ END-PERFORM. PROCESS-CUSTOMER-RECORD. ADD 1 TO RECORDS-READ ADD 1 TO TOTAL-CUSTOMERS ADD CM-ACCOUNT-BALANCE TO TOTAL-BALANCE DISPLAY 'Customer: ' CM-CUSTOMER-ID ' - ' CM-CUSTOMER-NAME DISPLAY 'Balance: ' CM-ACCOUNT-BALANCE DISPLAY 'Status: ' CM-ACCOUNT-STATUS *> Validate record structure IF CM-CUSTOMER-ID > 0 AND CM-CUSTOMER-ID < 99999999 IF CM-CUSTOMER-NAME NOT = SPACES ADD 1 TO RECORDS-PROCESSED DISPLAY 'Valid customer record processed' ELSE DISPLAY 'Invalid customer name detected' ADD 1 TO ERROR-COUNT END-IF ELSE DISPLAY 'Invalid customer ID detected' ADD 1 TO ERROR-COUNT END-IF. DEMONSTRATE-VARIABLE-RECORD-FD. DISPLAY 'Demonstrating variable record FD processing...' MOVE 'VARIABLE-RECORD' TO CURRENT-OPERATION OPEN INPUT TRANSACTION-FILE IF TRANS-SUCCESS DISPLAY 'Transaction file opened successfully' PERFORM READ-TRANSACTION-RECORDS CLOSE TRANSACTION-FILE ELSE DISPLAY 'Failed to open transaction file' DISPLAY 'Status: ' TRANSACTION-FILE-STATUS ADD 1 TO ERROR-COUNT END-IF. READ-TRANSACTION-RECORDS. DISPLAY 'Reading variable-length transaction records...' PERFORM UNTIL TRANS-EOF READ TRANSACTION-FILE AT END DISPLAY 'End of transaction file reached' NOT AT END PERFORM PROCESS-TRANSACTION-RECORD END-READ END-PERFORM. PROCESS-TRANSACTION-RECORD. ADD 1 TO RECORDS-READ ADD 1 TO TOTAL-TRANSACTIONS DISPLAY 'Transaction: ' TR-TRANSACTION-ID DISPLAY 'Type: ' TR-RECORD-TYPE DISPLAY 'Customer: ' TR-CUSTOMER-ID DISPLAY 'Amount: ' TR-AMOUNT DISPLAY 'Record Length: ' TR-RECORD-LENGTH *> Process based on transaction type EVALUATE TRUE WHEN DEPOSIT-RECORD ADD TR-AMOUNT TO TOTAL-DEPOSITS DISPLAY 'Deposit transaction processed' WHEN WITHDRAWAL-RECORD ADD TR-AMOUNT TO TOTAL-WITHDRAWALS DISPLAY 'Withdrawal transaction processed' WHEN TRANSFER-RECORD DISPLAY 'Transfer transaction processed' WHEN PAYMENT-RECORD DISPLAY 'Payment transaction processed' WHEN INQUIRY-RECORD DISPLAY 'Inquiry transaction processed' WHEN OTHER DISPLAY 'Unknown transaction type' ADD 1 TO ERROR-COUNT END-EVALUATE ADD 1 TO RECORDS-PROCESSED. DEMONSTRATE-REPORT-FD. DISPLAY 'Demonstrating report FD processing...' MOVE 'REPORT-WRITE' TO CURRENT-OPERATION OPEN OUTPUT REPORT-FILE IF REPORT-SUCCESS DISPLAY 'Report file opened successfully' PERFORM WRITE-REPORT-RECORDS CLOSE REPORT-FILE ELSE DISPLAY 'Failed to open report file' DISPLAY 'Status: ' REPORT-FILE-STATUS ADD 1 TO ERROR-COUNT END-IF. WRITE-REPORT-RECORDS. DISPLAY 'Writing report records with FD structure...' *> Write report header PERFORM WRITE-REPORT-HEADER *> Write sample detail records PERFORM WRITE-SAMPLE-DETAIL-RECORDS *> Write report summary PERFORM WRITE-REPORT-SUMMARY. WRITE-REPORT-HEADER. MOVE 'CUSTOMER ACCOUNT REPORT' TO RH-REPORT-TITLE MOVE REPORT-DATE TO RH-REPORT-DATE MOVE PAGE-NUMBER TO RH-PAGE-NUMBER WRITE REPORT-HEADER-RECORD IF REPORT-SUCCESS ADD 1 TO RECORDS-WRITTEN DISPLAY 'Report header written' ELSE DISPLAY 'Failed to write report header' ADD 1 TO ERROR-COUNT END-IF. WRITE-SAMPLE-DETAIL-RECORDS. *> Sample detail record 1 MOVE 12345678 TO RD-CUSTOMER-ID MOVE 'ACME CORPORATION' TO RD-CUSTOMER-NAME MOVE 150000.75 TO RD-ACCOUNT-BALANCE MOVE 'ACTIVE' TO RD-ACCOUNT-STATUS MOVE '2024-01-15' TO RD-LAST-ACTIVITY WRITE REPORT-DETAIL-RECORD IF REPORT-SUCCESS ADD 1 TO RECORDS-WRITTEN DISPLAY 'Detail record 1 written' ELSE DISPLAY 'Failed to write detail record 1' ADD 1 TO ERROR-COUNT END-IF *> Sample detail record 2 MOVE 23456789 TO RD-CUSTOMER-ID MOVE 'GLOBAL ENTERPRISES' TO RD-CUSTOMER-NAME MOVE 275000.50 TO RD-ACCOUNT-BALANCE MOVE 'ACTIVE' TO RD-ACCOUNT-STATUS MOVE '2024-01-14' TO RD-LAST-ACTIVITY WRITE REPORT-DETAIL-RECORD IF REPORT-SUCCESS ADD 1 TO RECORDS-WRITTEN DISPLAY 'Detail record 2 written' ELSE DISPLAY 'Failed to write detail record 2' ADD 1 TO ERROR-COUNT END-IF. WRITE-REPORT-SUMMARY. MOVE 'TOTALS:' TO RS-SUMMARY-LABEL MOVE TOTAL-CUSTOMERS TO RS-TOTAL-CUSTOMERS MOVE TOTAL-BALANCE TO RS-TOTAL-BALANCE IF TOTAL-CUSTOMERS > 0 COMPUTE AVERAGE-BALANCE = TOTAL-BALANCE / TOTAL-CUSTOMERS MOVE AVERAGE-BALANCE TO RS-AVERAGE-BALANCE ELSE MOVE 0 TO RS-AVERAGE-BALANCE END-IF WRITE REPORT-SUMMARY-RECORD IF REPORT-SUCCESS ADD 1 TO RECORDS-WRITTEN DISPLAY 'Report summary written' ELSE DISPLAY 'Failed to write report summary' ADD 1 TO ERROR-COUNT END-IF. DEMONSTRATE-INDEXED-FD. DISPLAY 'Demonstrating indexed FD processing...' MOVE 'INDEXED-ACCESS' TO CURRENT-OPERATION OPEN I-O INDEXED-CUSTOMER-FILE IF INDEXED-SUCCESS DISPLAY 'Indexed customer file opened successfully' PERFORM INDEXED-FILE-OPERATIONS CLOSE INDEXED-CUSTOMER-FILE ELSE DISPLAY 'Failed to open indexed customer file' DISPLAY 'Status: ' INDEXED-FILE-STATUS ADD 1 TO ERROR-COUNT END-IF. INDEXED-FILE-OPERATIONS. DISPLAY 'Performing indexed file operations...' *> Write a new record PERFORM WRITE-INDEXED-RECORD *> Read the record back PERFORM READ-INDEXED-RECORD *> Update the record PERFORM UPDATE-INDEXED-RECORD. WRITE-INDEXED-RECORD. MOVE 12345678 TO IDX-CUSTOMER-ID MOVE 'TECH SOLUTIONS INC' TO IDX-NAME MOVE '123 TECH STREET, SILICON VALLEY, CA 94000' TO IDX-ADDRESS MOVE '555-123-4567' TO IDX-PHONE MOVE 'contact@techsolutions.com' TO IDX-EMAIL MOVE 95000.25 TO IDX-BALANCE MOVE 150000.00 TO IDX-CREDIT-LIMIT MOVE 'ACTIVE' TO IDX-STATUS MOVE 'BUSINESS' TO IDX-TYPE MOVE 20240101 TO IDX-OPENED-DATE MOVE 20240110 TO IDX-LAST-PAYMENT MOVE 20240115 TO IDX-LAST-ACTIVITY MOVE 25 TO IDX-PAYMENT-COUNT MOVE 150 TO IDX-TRANSACTION-COUNT MOVE 10 TO IDX-INQUIRY-COUNT WRITE INDEXED-CUSTOMER-RECORD EVALUATE INDEXED-FILE-STATUS WHEN '00' ADD 1 TO RECORDS-WRITTEN DISPLAY 'Indexed record written successfully' WHEN '22' DISPLAY 'Record already exists' ADD 1 TO ERROR-COUNT WHEN OTHER DISPLAY 'Failed to write indexed record' DISPLAY 'Status: ' INDEXED-FILE-STATUS ADD 1 TO ERROR-COUNT END-EVALUATE. READ-INDEXED-RECORD. MOVE 12345678 TO IDX-CUSTOMER-ID READ INDEXED-CUSTOMER-FILE KEY IS IDX-CUSTOMER-ID EVALUATE INDEXED-FILE-STATUS WHEN '00' ADD 1 TO RECORDS-READ DISPLAY 'Indexed record read successfully' DISPLAY 'Customer: ' IDX-CUSTOMER-ID ' - ' IDX-NAME DISPLAY 'Balance: ' IDX-BALANCE DISPLAY 'Status: ' IDX-STATUS WHEN '23' DISPLAY 'Record not found' ADD 1 TO ERROR-COUNT WHEN OTHER DISPLAY 'Failed to read indexed record' DISPLAY 'Status: ' INDEXED-FILE-STATUS ADD 1 TO ERROR-COUNT END-EVALUATE. UPDATE-INDEXED-RECORD. MOVE 12345678 TO IDX-CUSTOMER-ID READ INDEXED-CUSTOMER-FILE KEY IS IDX-CUSTOMER-ID UPDATE IF INDEXED-SUCCESS ADD 1000.00 TO IDX-BALANCE ADD 1 TO IDX-TRANSACTION-COUNT MOVE 20240116 TO IDX-LAST-ACTIVITY REWRITE INDEXED-CUSTOMER-RECORD IF INDEXED-SUCCESS ADD 1 TO RECORDS-PROCESSED DISPLAY 'Indexed record updated successfully' DISPLAY 'New Balance: ' IDX-BALANCE ELSE DISPLAY 'Failed to update indexed record' DISPLAY 'Status: ' INDEXED-FILE-STATUS ADD 1 TO ERROR-COUNT END-IF ELSE DISPLAY 'Failed to read record for update' DISPLAY 'Status: ' INDEXED-FILE-STATUS ADD 1 TO ERROR-COUNT END-IF. DEMONSTRATE-ERROR-LOG-FD. DISPLAY 'Demonstrating error log FD processing...' MOVE 'ERROR-LOG' TO CURRENT-OPERATION OPEN EXTEND ERROR-LOG-FILE IF ERROR-LOG-SUCCESS DISPLAY 'Error log file opened successfully' PERFORM WRITE-ERROR-LOG-ENTRIES CLOSE ERROR-LOG-FILE ELSE DISPLAY 'Failed to open error log file' DISPLAY 'Status: ' ERROR-LOG-STATUS ADD 1 TO ERROR-COUNT END-IF. WRITE-ERROR-LOG-ENTRIES. DISPLAY 'Writing error log entries...' *> Write info entry MOVE FUNCTION CURRENT-DATE TO EL-TIMESTAMP SET EL-INFO TO TRUE MOVE 'FDPROG' TO EL-PROGRAM-NAME MOVE 'FD-PROCESSING' TO EL-MODULE-NAME MOVE 1001 TO EL-ERROR-CODE MOVE 'FD processing demonstration started' TO EL-ERROR-MESSAGE MOVE 'SESSION-001' TO EL-ADDITIONAL-DATA WRITE ERROR-LOG-RECORD IF ERROR-LOG-SUCCESS ADD 1 TO RECORDS-WRITTEN DISPLAY 'Info log entry written' ELSE DISPLAY 'Failed to write info log entry' ADD 1 TO ERROR-COUNT END-IF *> Write warning entry MOVE FUNCTION CURRENT-DATE TO EL-TIMESTAMP SET EL-WARNING TO TRUE MOVE 'FDPROG' TO EL-PROGRAM-NAME MOVE 'FD-PROCESSING' TO EL-MODULE-NAME MOVE 2001 TO EL-ERROR-CODE MOVE 'Variable record length detected' TO EL-ERROR-MESSAGE MOVE 'TRANS-FILE' TO EL-ADDITIONAL-DATA WRITE ERROR-LOG-RECORD IF ERROR-LOG-SUCCESS ADD 1 TO RECORDS-WRITTEN DISPLAY 'Warning log entry written' ELSE DISPLAY 'Failed to write warning log entry' ADD 1 TO ERROR-COUNT END-IF. DISPLAY-FD-STATISTICS. DISPLAY 'FD Processing Statistics:' DISPLAY '========================' DISPLAY 'Records read: ' RECORDS-READ DISPLAY 'Records written: ' RECORDS-WRITTEN DISPLAY 'Records processed: ' RECORDS-PROCESSED DISPLAY 'Error count: ' ERROR-COUNT DISPLAY 'Total customers: ' TOTAL-CUSTOMERS DISPLAY 'Total balance: ' TOTAL-BALANCE DISPLAY 'Total transactions: ' TOTAL-TRANSACTIONS DISPLAY 'Total deposits: ' TOTAL-DEPOSITS DISPLAY 'Total withdrawals: ' TOTAL-WITHDRAWALS IF TOTAL-CUSTOMERS > 0 COMPUTE AVERAGE-BALANCE = TOTAL-BALANCE / TOTAL-CUSTOMERS DISPLAY 'Average balance: ' AVERAGE-BALANCE END-IF DISPLAY 'Last operation: ' CURRENT-OPERATION.

Best Practices and FAQ

FD Best Practices
  • • Use descriptive file and record names
  • • Specify appropriate block and record sizes
  • • Include all necessary FD clauses
  • • Document record layouts clearly
  • • Use FILLER for unused record areas
File Structure Guidelines
  • • Design efficient record layouts
  • • Consider data alignment and padding
  • • Use appropriate data types and sizes
  • • Plan for future record expansion
  • • Implement proper key structures