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COBOL – Table Processing ”; Previous Next Arrays in COBOL are known as tables. An array is a linear data structure and is a collection of individual data items of same type. Data items of a table are internally sorted. Table Declaration Table is declared in Data Division. Occurs clause is used to define a table. Occurs clause indicates the repetition of data name definition. It can be used only with level numbers starting from 02 to 49. Do not use occurs clause with Redefines. Description of one-dimensional and two-dimensional table is as follows − One-Dimensional Table In a one-dimensional table, occurs clause is used only once in declaration. WSTABLE is the group item that contains table. WS-B names the table elements that occur 10 times. Syntax Following is the syntax for defining a one-dimensional table − 01 WS-TABLE. 05 WS-A PIC A(10) OCCURS 10 TIMES. Example Live Demo IDENTIFICATION DIVISION. PROGRAM-ID. HELLO. DATA DIVISION. WORKING-STORAGE SECTION. 01 WS-TABLE. 05 WS-A PIC A(10) VALUE ”TUTORIALS” OCCURS 5 TIMES. PROCEDURE DIVISION. DISPLAY “ONE-D TABLE : “WS-TABLE. STOP RUN. JCL to execute the above COBOL program − //SAMPLE JOB(TESTJCL,XXXXXX),CLASS = A,MSGCLASS = C //STEP1 EXEC PGM = HELLO When you compile and execute the above program, it produces the following result − ONE-D TABLE : TUTORIALS TUTORIALS TUTORIALS TUTORIALS TUTORIALS Two-Dimensional Table A two-dimensional table is created with both data elements being variable length. For reference, go through the syntax and then try to analyze the table. The first array (WS-A) can occur from 1 to 10 times and the inner array (WS-C) can occur from 1 to 5 times. For each entry of WS-A, there will be corresponding 5 entries of WS-C. Syntax Following is the syntax for defining a two-dimensional table − 01 WS-TABLE. 05 WS-A OCCURS 10 TIMES. 10 WS-B PIC A(10). 10 WS-C OCCURS 5 TIMES. 15 WS-D PIC X(6). Example Live Demo IDENTIFICATION DIVISION. PROGRAM-ID. HELLO. DATA DIVISION. WORKING-STORAGE SECTION. 01 WS-TABLE. 05 WS-A OCCURS 2 TIMES. 10 WS-B PIC A(10) VALUE ” TUTORIALS”. 10 WS-C OCCURS 2 TIMES. 15 WS-D PIC X(6) VALUE ” POINT”. PROCEDURE DIVISION. DISPLAY “TWO-D TABLE : “WS-TABLE. STOP RUN. JCL to execute the above COBOL program − //SAMPLE JOB(TESTJCL,XXXXXX),CLASS = A,MSGCLASS = C //STEP1 EXEC PGM = HELLO When you compile and execute the above program, it produces the following result − TWO-D TABLE : TUTORIALS POINT POINT TUTORIALS POINT POINT Subscript Table individual elements can be accessed by using subscript. Subscript values can range from 1 to the number of times the table occurs. A subscript can be any positive number. It does not require any declaration in data division. It is automatically created with occurs clause. Example Live Demo IDENTIFICATION DIVISION. PROGRAM-ID. HELLO. DATA DIVISION. WORKING-STORAGE SECTION. 01 WS-TABLE. 05 WS-A OCCURS 3 TIMES. 10 WS-B PIC A(2). 10 WS-C OCCURS 2 TIMES. 15 WS-D PIC X(3). PROCEDURE DIVISION. MOVE ”12ABCDEF34GHIJKL56MNOPQR” TO WS-TABLE. DISPLAY ”WS-TABLE : ” WS-TABLE. DISPLAY ”WS-A(1) : ” WS-A(1). DISPLAY ”WS-C(1,1) : ” WS-C(1,1). DISPLAY ”WS-C(1,2) : ” WS-C(1,2). DISPLAY ”WS-A(2) : ” WS-A(2). DISPLAY ”WS-C(2,1) : ” WS-C(2,1). DISPLAY ”WS-C(2,2) : ” WS-C(2,2). DISPLAY ”WS-A(3) : ” WS-A(3). DISPLAY ”WS-C(3,1) : ” WS-C(3,1). DISPLAY ”WS-C(3,2) : ” WS-C(3,2). STOP RUN. JCL to execute the above COBOL program − //SAMPLE JOB(TESTJCL,XXXXXX),CLASS = A,MSGCLASS = C //STEP1 EXEC PGM = HELLO When you compile and execute the above program, it produces the following result − WS-TABLE : 12ABCDEF34GHIJKL56MNOPQR WS-A(1) : 12ABCDEF WS-C(1,1) : ABC WS-C(1,2) : DEF WS-A(2) : 34GHIJKL WS-C(2,1) : GHI WS-C(2,2) : JKL WS-A(3) : 56MNOPQR WS-C(3,1) : MNO WS-C(3,2) : PQR Index Table elements can also be accessed using index. An index is a displacement of element from the start of the table. An index is declared with Occurs clause using INDEXED BY clause. The value of index can be changed using SET statement and PERFORM Varying option. Syntax Following is the syntax for defining Index in a table − 01 WS-TABLE. 05 WS-A PIC A(10) OCCURS 10 TIMES INDEXED BY I. Example Live Demo IDENTIFICATION DIVISION. PROGRAM-ID. HELLO. DATA DIVISION. WORKING-STORAGE SECTION. 01 WS-TABLE. 05 WS-A OCCURS 3 TIMES INDEXED BY I. 10 WS-B PIC A(2). 10 WS-C OCCURS 2 TIMES INDEXED BY J. 15 WS-D PIC X(3). PROCEDURE DIVISION. MOVE ”12ABCDEF34GHIJKL56MNOPQR” TO WS-TABLE. PERFORM A-PARA VARYING I FROM 1 BY 1 UNTIL I >3 STOP RUN. A-PARA. PERFORM C-PARA VARYING J FROM 1 BY 1 UNTIL J>2. C-PARA. DISPLAY WS-C(I,J). JCL to execute the above COBOL program − //SAMPLE JOB(TESTJCL,XXXXXX),CLASS = A,MSGCLASS = C //STEP1 EXEC PGM = HELLO When you compile and execute the above program, it produces the following result − ABC DEF GHI JKL MNO PQR Set Statement Set statement is used to change the index value. Set verb is used to initialize, increment, or decrement the index value. It is used with Search and Search All to locate elements in table. Syntax Following is the syntax for using a Set statement − SET I J TO positive-number SET I TO J SET I TO 5 SET I J UP BY 1 SET J DOWN BY 5 Example Live Demo IDENTIFICATION DIVISION. PROGRAM-ID. HELLO. DATA DIVISION. WORKING-STORAGE SECTION. 01 WS-TABLE. 05 WS-A OCCURS 3 TIMES INDEXED BY I. 10 WS-B PIC A(2). 10 WS-C OCCURS 2 TIMES INDEXED BY J. 15 WS-D PIC X(3). PROCEDURE DIVISION. MOVE ”12ABCDEF34GHIJKL56MNOPQR” TO WS-TABLE. SET I J TO 1. DISPLAY WS-C(I,J). SET I J UP BY 1. DISPLAY WS-C(I,J). STOP RUN. JCL to execute the above COBOL program. //SAMPLE JOB(TESTJCL,XXXXXX),CLASS = A,MSGCLASS = C //STEP1 EXEC PGM = HELLO When you compile and execute the above program, it produces the following result − ABC JKL Search Search is a linear search method, which is used to find elements inside the table. It can be performed on sorted as well as unsorted table. It is used only for tables declared by Index phrase. It starts with the initial value of index. If the searched element is not found,