MainframeMaster

COBOL Data Representation

Data representation defines how data is stored, formatted, and interpreted in COBOL programs using PICTURE clauses, data types, and storage formats. Learn to represent different kinds of information effectively.

Numeric Data Representation

cobol
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
       WORKING-STORAGE SECTION.
       01 NUMERIC-DATA-REPRESENTATION.
           05 INTEGER-NUMBERS.
               10 SMALL-INTEGER PIC 9(4).           *> 4-digit integer
               10 LARGE-INTEGER PIC 9(8).           *> 8-digit integer
               10 SIGNED-INTEGER PIC S9(6).         *> Signed 6-digit integer
           05 DECIMAL-NUMBERS.
               10 DECIMAL-AMOUNT PIC 9(6)V99.       *> 6 digits, 2 decimal places
               10 PRECISE-DECIMAL PIC 9(9)V999.     *> 9 digits, 3 decimal places
               10 SIGNED-DECIMAL PIC S9(7)V99.      *> Signed decimal
           05 COMPUTATIONAL-NUMBERS.
               10 COMP-NUMBER PIC 9(6) COMP.        *> Binary representation
               10 COMP3-NUMBER PIC 9(6) COMP-3.     *> Packed decimal
               10 COMP5-NUMBER PIC 9(6) COMP-5.      *> Native binary
       
       PROCEDURE DIVISION.
       PERFORM DEMONSTRATE-NUMERIC-REPRESENTATION
       
       DEMONSTRATE-NUMERIC-REPRESENTATION.
           MOVE 1234 TO SMALL-INTEGER
           MOVE 12345678 TO LARGE-INTEGER
           MOVE -50000 TO SIGNED-INTEGER
           MOVE 1500.50 TO DECIMAL-AMOUNT
           MOVE 123456.789 TO PRECISE-DECIMAL
           MOVE -7500.25 TO SIGNED-DECIMAL
           
           DISPLAY 'Numeric data representation:'
           DISPLAY 'Small Integer: ' SMALL-INTEGER
           DISPLAY 'Large Integer: ' LARGE-INTEGER
           DISPLAY 'Signed Integer: ' SIGNED-INTEGER
           DISPLAY 'Decimal Amount: ' DECIMAL-AMOUNT
           DISPLAY 'Precise Decimal: ' PRECISE-DECIMAL
           DISPLAY 'Signed Decimal: ' SIGNED-DECIMAL.

Represent numeric data using different PICTURE clauses: 9 for digits, V for decimal point, S for sign, and COMP/COMP-3/COMP-5 for different storage formats. Choose appropriate formats for data precision and storage efficiency.

Character Data Representation

cobol
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
       WORKING-STORAGE SECTION.
       01 CHARACTER-DATA-REPRESENTATION.
           05 ALPHANUMERIC-DATA.
               10 CUSTOMER-NAME PIC X(30).          *> Alphanumeric field
               10 ADDRESS PIC X(50).                 *> Alphanumeric field
               10 PHONE-NUMBER PIC X(12).           *> Alphanumeric field
           05 ALPHABETIC-DATA.
               10 FIRST-NAME PIC A(15).             *> Alphabetic only
               10 LAST-NAME PIC A(20).              *> Alphabetic only
               10 MIDDLE-INITIAL PIC A.             *> Single character
           05 MIXED-DATA.
               10 PRODUCT-CODE PIC X(10).           *> Mixed characters
               10 SERIAL-NUMBER PIC X(15).          *> Mixed characters
               10 DESCRIPTION PIC X(100).           *> Mixed characters
       
       PROCEDURE DIVISION.
       PERFORM DEMONSTRATE-CHARACTER-REPRESENTATION
       
       DEMONSTRATE-CHARACTER-REPRESENTATION.
           MOVE 'JOHN SMITH' TO CUSTOMER-NAME
           MOVE '123 MAIN STREET' TO ADDRESS
           MOVE '(555) 123-4567' TO PHONE-NUMBER
           MOVE 'JOHN' TO FIRST-NAME
           MOVE 'SMITH' TO LAST-NAME
           MOVE 'A' TO MIDDLE-INITIAL
           MOVE 'PROD-001' TO PRODUCT-CODE
           MOVE 'SN123456789' TO SERIAL-NUMBER
           
           DISPLAY 'Character data representation:'
           DISPLAY 'Customer Name: ' CUSTOMER-NAME
           DISPLAY 'Address: ' ADDRESS
           DISPLAY 'Phone: ' PHONE-NUMBER
           DISPLAY 'First Name: ' FIRST-NAME
           DISPLAY 'Last Name: ' LAST-NAME
           DISPLAY 'Middle Initial: ' MIDDLE-INITIAL
           DISPLAY 'Product Code: ' PRODUCT-CODE
           DISPLAY 'Serial Number: ' SERIAL-NUMBER.

Represent character data using X for alphanumeric fields (letters, digits, special characters) and A for alphabetic fields (letters only). Use appropriate field sizes for different data types.

Edited Data Representation

cobol
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
       WORKING-STORAGE SECTION.
       01 EDITED-DATA-REPRESENTATION.
           05 CURRENCY-FORMAT.
               10 RAW-AMOUNT PIC 9(9)V99.
               10 EDITED-AMOUNT PIC $,$$$,$$9.99.   *> Currency format
               10 SIMPLE-CURRENCY PIC $999.99.      *> Simple currency
           05 DATE-FORMAT.
               10 RAW-DATE PIC 9(8).
               10 EDITED-DATE PIC 99/99/9999.       *> Date format
               10 LONG-DATE PIC 99/99/9999.         *> Long date format
           05 PHONE-FORMAT.
               10 RAW-PHONE PIC 9(10).
               10 EDITED-PHONE PIC (999) 999-9999.  *> Phone format
               10 SIMPLE-PHONE PIC 999-999-9999.   *> Simple phone
           05 SPECIAL-FORMATS.
               10 ZERO-SUPPRESSED PIC ZZZZZ9.       *> Zero suppression
               10 SIGNED-FORMAT PIC +,$$$,$$9.99.   *> Signed format
               10 NEGATIVE-FORMAT PIC -,$$$,$$9.99. *> Negative format
       
       PROCEDURE DIVISION.
       PERFORM DEMONSTRATE-EDITED-REPRESENTATION
       
       DEMONSTRATE-EDITED-REPRESENTATION.
           MOVE 1234567.89 TO RAW-AMOUNT
           MOVE RAW-AMOUNT TO EDITED-AMOUNT
           MOVE 20231225 TO RAW-DATE
           MOVE RAW-DATE TO EDITED-DATE
           MOVE 1234567890 TO RAW-PHONE
           MOVE RAW-PHONE TO EDITED-PHONE
           
           DISPLAY 'Edited data representation:'
           DISPLAY 'Raw Amount: ' RAW-AMOUNT
           DISPLAY 'Edited Amount: ' EDITED-AMOUNT
           DISPLAY 'Raw Date: ' RAW-DATE
           DISPLAY 'Edited Date: ' EDITED-DATE
           DISPLAY 'Raw Phone: ' RAW-PHONE
           DISPLAY 'Edited Phone: ' EDITED-PHONE.

Use edited data representation with special characters for formatting: $ for currency, / for dates, () for phone numbers, Z for zero suppression, and + or - for sign indicators.

Data Storage Formats

cobol
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
       WORKING-STORAGE SECTION.
       01 DATA-STORAGE-FORMATS.
           05 DISPLAY-FORMAT.
               10 DISPLAY-NUMERIC PIC 9(6).         *> Character format
               10 DISPLAY-ALPHANUMERIC PIC X(20).    *> Character format
           05 COMPUTATIONAL-FORMATS.
               10 COMP-BINARY PIC 9(6) COMP.        *> Binary format
               10 COMP-PACKED PIC 9(6) COMP-3.       *> Packed decimal
               10 COMP-NATIVE PIC 9(6) COMP-5.       *> Native binary
           05 SPECIAL-FORMATS.
               10 INDEX-FORMAT PIC 9(6) INDEX.       *> Index value
               10 POINTER-FORMAT USAGE POINTER.     *> Memory address
               10 PROCEDURE-POINTER USAGE PROCEDURE-POINTER.
       
       PROCEDURE DIVISION.
       PERFORM DEMONSTRATE-STORAGE-FORMATS
       
       DEMONSTRATE-STORAGE-FORMATS.
           MOVE 123456 TO DISPLAY-NUMERIC
           MOVE 'HELLO WORLD' TO DISPLAY-ALPHANUMERIC
           MOVE 123456 TO COMP-BINARY
           MOVE 123456 TO COMP-PACKED
           MOVE 123456 TO COMP-NATIVE
           
           DISPLAY 'Data storage formats:'
           DISPLAY 'Display Numeric: ' DISPLAY-NUMERIC
           DISPLAY 'Display Alphanumeric: ' DISPLAY-ALPHANUMERIC
           DISPLAY 'COMP Binary: ' COMP-BINARY
           DISPLAY 'COMP Packed: ' COMP-PACKED
           DISPLAY 'COMP Native: ' COMP-NATIVE.

Choose appropriate storage formats based on usage: DISPLAY for character representation, COMP for binary storage, COMP-3 for packed decimal, INDEX for table indexing, and POINTER for memory addresses.

Data Type Conversion

cobol
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
       WORKING-STORAGE SECTION.
       01 DATA-TYPE-CONVERSION.
           05 SOURCE-DATA.
               10 STRING-NUMBER PIC X(10).
               10 NUMERIC-VALUE PIC 9(6).
               10 ALPHANUMERIC-DATA PIC X(20).
           05 CONVERTED-DATA.
               10 CONVERTED-NUMBER PIC 9(6).
               10 CONVERTED-STRING PIC X(10).
               10 UPPERCASE-DATA PIC X(20).
               10 LOWERCASE-DATA PIC X(20).
       
       PROCEDURE DIVISION.
       PERFORM DEMONSTRATE-DATA-TYPE-CONVERSION
       
       DEMONSTRATE-DATA-TYPE-CONVERSION.
           MOVE '123456' TO STRING-NUMBER
           MOVE 789012 TO NUMERIC-VALUE
           MOVE 'Hello World' TO ALPHANUMERIC-DATA
           
           *> Convert string to numeric
           MOVE STRING-NUMBER TO CONVERTED-NUMBER
           
           *> Convert numeric to string
           MOVE NUMERIC-VALUE TO CONVERTED-STRING
           
           *> Convert to uppercase
           MOVE FUNCTION UPPER-CASE(ALPHANUMERIC-DATA) TO UPPERCASE-DATA
           
           *> Convert to lowercase
           MOVE FUNCTION LOWER-CASE(ALPHANUMERIC-DATA) TO LOWERCASE-DATA
           
           DISPLAY 'Data type conversion:'
           DISPLAY 'String to Number: ' CONVERTED-NUMBER
           DISPLAY 'Number to String: ' CONVERTED-STRING
           DISPLAY 'Uppercase: ' UPPERCASE-DATA
           DISPLAY 'Lowercase: ' LOWERCASE-DATA.

Convert between different data types using MOVE statements and intrinsic functions. Convert strings to numbers, numbers to strings, and change case using UPPER-CASE and LOWER-CASE functions.

Data Representation Best Practices

cobol
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
       WORKING-STORAGE SECTION.
       01 DATA-REPRESENTATION-BEST-PRACTICES.
           05 WELL-DEFINED-DATA.
               10 CUSTOMER-ID PIC 9(6).             *> Clear numeric ID
               10 CUSTOMER-NAME PIC X(30).          *> Appropriate size
               10 ACCOUNT-BALANCE PIC 9(9)V99.      *> Sufficient precision
               10 ACCOUNT-STATUS PIC X.             *> Single character
                   88 STATUS-ACTIVE VALUE 'A'.
                   88 STATUS-INACTIVE VALUE 'I'.
           05 CONSISTENT-FORMATS.
               10 DATE-FIELD PIC 9(8).              *> YYYYMMDD format
               10 TIME-FIELD PIC 9(6).              *> HHMMSS format
               10 AMOUNT-FIELD PIC 9(9)V99.         *> Consistent decimal places
           05 APPROPRIATE-SIZES.
               10 SHORT-FIELD PIC X(10).            *> Appropriate for short data
               10 MEDIUM-FIELD PIC X(50).           *> Appropriate for medium data
               10 LONG-FIELD PIC X(200).            *> Appropriate for long data
       
       PROCEDURE DIVISION.
       PERFORM DEMONSTRATE-BEST-PRACTICES
       
       DEMONSTRATE-BEST-PRACTICES.
           MOVE 123456 TO CUSTOMER-ID
           MOVE 'JOHN SMITH' TO CUSTOMER-NAME
           MOVE 1500.50 TO ACCOUNT-BALANCE
           MOVE 'A' TO ACCOUNT-STATUS
           
           DISPLAY 'Best practices demonstration:'
           DISPLAY 'Customer ID: ' CUSTOMER-ID
           DISPLAY 'Customer Name: ' CUSTOMER-NAME
           DISPLAY 'Account Balance: ' ACCOUNT-BALANCE
           DISPLAY 'Account Status: ' ACCOUNT-STATUS
           
           IF STATUS-ACTIVE
               DISPLAY 'Account is active'
           END-IF.

Follow best practices: use appropriate data types and sizes, maintain consistent formats, define clear field purposes, use condition names for flags, and choose efficient storage formats.

Data Representation Documentation

cobol
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
       WORKING-STORAGE SECTION.
       01 DOCUMENTED-DATA-REPRESENTATION.
           05 CUSTOMER-MASTER-DATA.
               *> Customer identification and basic information
               10 CUSTOMER-ID PIC 9(6).
                   *> Unique customer identifier (1-999999)
               10 CUSTOMER-NAME PIC X(30).
                   *> Customer full name (last, first middle)
               10 CUSTOMER-PHONE PIC X(12).
                   *> Customer phone number (XXX-XXX-XXXX)
               10 CUSTOMER-EMAIL PIC X(40).
                   *> Customer email address
           05 FINANCIAL-DATA.
               *> Customer financial information
               10 ACCOUNT-BALANCE PIC 9(9)V99.
                   *> Current account balance (0-999999.99)
               10 CREDIT-LIMIT PIC 9(9)V99.
                   *> Credit limit (0-999999.99)
               10 PAYMENT-TERMS PIC X(10).
                   *> Payment terms (NET30, NET60, etc.)
       
       PROCEDURE DIVISION.
       PERFORM DEMONSTRATE-DOCUMENTED-REPRESENTATION
       
       DEMONSTRATE-DOCUMENTED-REPRESENTATION.
           MOVE 123456 TO CUSTOMER-ID
           MOVE 'JOHN SMITH' TO CUSTOMER-NAME
           MOVE '555-123-4567' TO CUSTOMER-PHONE
           MOVE 'john@email.com' TO CUSTOMER-EMAIL
           MOVE 1500.50 TO ACCOUNT-BALANCE
           MOVE 5000.00 TO CREDIT-LIMIT
           MOVE 'NET30' TO PAYMENT-TERMS
           
           DISPLAY 'Documented data representation:'
           DISPLAY 'Customer ID: ' CUSTOMER-ID
           DISPLAY 'Customer Name: ' CUSTOMER-NAME
           DISPLAY 'Phone: ' CUSTOMER-PHONE
           DISPLAY 'Email: ' CUSTOMER-EMAIL
           DISPLAY 'Balance: ' ACCOUNT-BALANCE
           DISPLAY 'Credit Limit: ' CREDIT-LIMIT
           DISPLAY 'Payment Terms: ' PAYMENT-TERMS.

Document data representation with clear comments explaining field purposes, data ranges, formats, and business rules. Include examples and constraints for better understanding and maintenance.

Performance Considerations

cobol
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
       WORKING-STORAGE SECTION.
       01 PERFORMANCE-CONSIDERATIONS.
           05 EFFICIENT-DATA-TYPES.
               10 COMP-NUMERIC PIC 9(6) COMP.       *> Efficient for calculations
               10 DISPLAY-NUMERIC PIC 9(6).         *> Efficient for display
               10 PACKED-DECIMAL PIC 9(6)V99 COMP-3. *> Efficient for financial
           05 APPROPRIATE-SIZES.
               10 SMALL-FIELD PIC X(10).            *> Minimal memory usage
               10 MEDIUM-FIELD PIC X(50).           *> Balanced size
               10 LARGE-FIELD PIC X(200).           *> Sufficient for large data
           05 STORAGE-OPTIMIZATION.
               10 GROUPED-DATA PIC X(100).          *> Group related data
               10 ALIGNED-DATA PIC X(100).           *> Proper alignment
       
       PROCEDURE DIVISION.
       PERFORM DEMONSTRATE-PERFORMANCE-CONSIDERATIONS
       
       DEMONSTRATE-PERFORMANCE-CONSIDERATIONS.
           MOVE 123456 TO COMP-NUMERIC
           MOVE 123456 TO DISPLAY-NUMERIC
           MOVE 1234.56 TO PACKED-DECIMAL
           
           DISPLAY 'Performance considerations:'
           DISPLAY 'COMP Numeric: ' COMP-NUMERIC
           DISPLAY 'Display Numeric: ' DISPLAY-NUMERIC
           DISPLAY 'Packed Decimal: ' PACKED-DECIMAL.

Consider performance when choosing data representations: use COMP for calculations, DISPLAY for I/O operations, appropriate field sizes for memory usage, and efficient storage formats for different data types.

Data Qualification

Data validation and verification

Data Types Representation

Data types and representations