Data Movement Statements

Data movement statements are responsible for transferring data between data items. These are –

• INITIALIZE Statement
• MOVE Statement

INITIALIZE Statement

INITIALIZE sets all elementary variables under group variable with system-defined initial values based on their data types. It is convenient to reset the full copybook and group variable to ensure they start with predictable values.

Syntax -

INITIALIZE group-variable-1 [group-variable-2 ...]

• group-variable-1, group-variable-2, ...- Refers to the variable names we wish to initialize.

Example - Initialize usage in COBOL program.

----+----1----+----2----+----3----+----4----+----5----+
       ...
       WORKING-STORAGE SECTION.
       01 WS-VAR.
          05 WS-NAME        PIC X(20). 
          05 FILLER         PIC X(05). 
          05 WS-GENDER      PIC X(01). 
          05 FILLER         PIC X(05). 
          05 WS-TODAY       PIC 9(08). 
          05 FILLER         PIC X(01). 
       ...
       PROCEDURE DIVISION.
           MOVE ALL '-'         TO WS-VAR.
           DISPLAY 'BEFORE INIT:  ' WS-VAR.

           INITIALIZE WS-VAR.
           DISPLAY 'AFTER INIT:   ' WS-VAR.
		   ...

JCL -

//MATEPKRJ JOB MSGLEVEL=(1,1),NOTIFY=&SYSUID
//**
//STEP01  EXEC PGM=INITGRP
//STEPLIB  DD  DSN=MATEPK.COBOL.LOADLIB,DISP=SHR
//SYSOUT   DD  SYSOUT=*

Output -

BEFORE INIT:  ----------------------------------------
AFTER INIT:                       ----- -----00000000-

MOVE Statement

MOVE statement is used to transfer data from the source data item to the target data item. It ensures that data is transformed appropriately or converted based on the receiving data item's type and format.

It is divided into four types based on its usage -

• Simple MOVE
• Group MOVE
• MOVE Corresponding
• MOVE Reference Modification

Simple MOVE

It is used to move the value of the sending item(s) to the receiving item. The sending and receiving data items should be declared with compatible data type to avoid data transferring errors.

Syntax -

MOVE sending-item TO receiving-item.

Example - Moving the alpha-numeric string to another variable.

----+----1----+----2----+----3----+----4----+----5----+
       ...
       WORKING-STORAGE SECTION.
       01 WS-SENDING-VAR       PIC X(5)    VALUE 'Hello'.
       01 WS-RECEIVING-VAR     PIC X(10).
       ...
       PROCEDURE DIVISION.
           MOVE WS-SENDING-VAR TO WS-RECEIVING-VAR.
           DISPLAY "WS-RECEIVING-VAR: " WS-RECEIVING-VAR.
		   ...

After the MOVE, WS-RECEIVING-VAR will contain 'Hello' followed by 5 spaces.

Group MOVE

It is used to move data between two groups whose elementary items are in the same order. However, the elementary items in both groups should have the same names and data type.

Syntax -

MOVE sending-group TO receiving-group

Example - Moving data from one group to another group.

----+----1----+----2----+----3----+----4----+----5----+
       ...
       WORKING-STORAGE SECTION.
       01 WS-GRP1.
          05 NUM        PIC 9(02) VALUE 1.
          05 NAME       PIC X(20) VALUE 'MAINFRAMESTECHHELP'.
       01 WS-GRP2.
          05 NUM        PIC 9(02).
          05 NAME       PIC X(20).
       ...
       PROCEDURE DIVISION.
           MOVE WS-GRP1     TO WS-GRP2.
		   ...

After the MOVE, WS-GRP2 will contain 01MAINFRAMESTECHHELP.

MOVE Corresponding

It is used to move data between two groups whose elementary items are not in the same order. However, the elementary items in both groups should have the same names and data type.

Syntax -

MOVE CORRESPONDING|CORR sending-group TO receiving-group

Example - Changing the date format from MM-DD-YYYY to DD/MM/YYYY.

----+----1----+----2----+----3----+----4----+----5----+
       ...
       WORKING-STORAGE SECTION.
       01 WS-DATE-MDY.
          05 WS-DATE-MM          PIC 9(02)  VALUE 10.  
          05 FILLER              PIC X      VALUE '-'. 
          05 WS-DATE-DD          PIC 9(02)  VALUE 13.  
          05 FILLER              PIC X      VALUE '-'. 
          05 WS-DATE-YYYY        PIC 9(04)  VALUE 2023.
       01 WS-DATE-DMY.
          05 WS-DATE-DD          PIC 9(02).
          05 FILLER              PIC X      VALUE '/'. 
          05 WS-DATE-MM          PIC 9(02).
          05 FILLER              PIC X      VALUE '/'.
          05 WS-DATE-YYYY        PIC 9(04).
       ...
       PROCEDURE DIVISION.
           MOVE CORR WS-DATE-MDY TO WS-DATE-DMY.
		   ...

After the MOVE, WS-DATE-DMY will contain 13/10/2023.

MOVE Referencing Modification

It is a special-purpose MOVE that moves a portion of data from the sending item to the receiving item. It is mainly useful when dealing with strings, where we might want to handle only a specific part of the data.

Syntax -

variable (start-position [: length])

Example - Formatting full phone number from three different sources.

----+----1----+----2----+----3----+----4----+----5----+
       ...
       WORKING-STORAGE SECTION.
       01 WS-COUNTRY-CODE        PIC 9(02)  VALUE 91.
       01 WS-AREA-CODE           PIC 9(03)  VALUE 999.
       01 WS-PHONE-NBR           PIC 9(08)  VALUE 87654321.
       01 WS-FULL-PHN-NBR        PIC 9(13).
       ...
       PROCEDURE DIVISION.
           MOVE WS-COUNTRY-CODE  TO WS-FULL-PHN-NBR(1:2).
           MOVE WS-AREA-CODE     TO WS-FULL-PHN-NBR(3:2).
           MOVE WS-PHONE-NBR     TO WS-FULL-PHN-NBR(5:8).
		   ...

After the MOVE, WS-FULL-PHN-NBR will contain 919987654321.

MOVE Combinations -

This table represents the souce item data types(left) and target item data types(top). Y = Move is valid, N = Move is invalid.

• Data Movement Statements
  • INITIALIZE Statement
  • MOVE Statement
    • Simple MOVE
    • Group MOVE
    • MOVE Corresponding
    • MOVE Reference Modification