Answer Posted / rajini
The SYNCHRONIZED clause is sometimes used with USAGE IS
COMP or USAGE IS INDEX items. It is used to optimize speed
of processing but it does so at the expense of increased
storage requirements.
Many computer memories are organized in such a way that
there are natural addressing boundaries - such as word
boundaries. If no special action is taken some data items
in memory may straddle theses boundaries. This may cause a
processing overhead as the CPU may need two fetch cycles to
retrieve the data from memory.
The SYNCHRONIZED clause is used to explicitly align COMP
and INDEX items along their natural word boundaries.
Without the SYNCHRONIZED clause, data-items are aligned on
byte boundaries.
The word SYNC can be used instead of SYNCHRONIZED.
For the purpose of illustrating how the SYNCHRONIZED clause
works let us assume that a COBOL program is running on a
word-oriented computer where the CPU fetches data from
memory a word at a time.
01 three-byte pic x(3) value 'dog'.
01 two-byte pic s9(4) comp .
In this program we want to perform a calculation on the
number stored in the variable TwoBytes (as declared in the
diagram below). Because of the way the data items have been
declared, the number stored in TwoBytes straddles a word
boundary.
In order to use the number, the CPU has to execute two
fetch cycles - one to get the first part of the number in
Word2 and the second to get the second part of the number
in Word3. This double fetch slows down calculations.
01 three-byte pic x(3) value 'dog'.
01 two-byte pic s9(4) comp sync .
Now consider the impact of using the SYNCHRONIZED clause.
The number in TwoBytes is now aligned along the word
boundary, so the CPU only has to do one fetch cycle to
retrieve the number from memory. This speeds up processing
but at the expense of wasting some storage (the second byte
of Word2 is no longer used).
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IDENTIFICATION DIVISION. PROGRAM-ID. UPDT. AUTHOR.anbu. DATE-WRITTEN. AUG 13. ENVIRONMENT DIVISION. INPUT-OUTPUT SECTION. FILE-CONTROL. SELECT CMSTR ASSIGN TO CINP1 ORGANIZATION IS INDEXED ACCESS IS SEQUENTIAL RECORD KEY CM2-KEY FILE STATUS IS WS-CMSTR-FST. SELECT CTAB ASSIGN TO CINP2 ORGANIZATION IS ACCESS IS SEQUENTIAL RECORD KEY VSAM-WHSE- KEY FILE STATUS IS WS-CTAB- FST. DATA DIVISION. FILE SECTION. FD CMSTR. COPY RXCYFC20. FD CTAB. COPY AITYWHSE. ************************************************************ ****** *** WORKING STORAGE VARIABLES *** ************************************************************ ****** WORKING-STORAGE SECTION. 01 WS- VARIABLES. 05 WS-EB PIC X(02) VALUE ZEROES. 05 WS-DIV PIC 9(03) VALUE ZEROES. 05 WS-CMF-RECS-REWRITTEN PIC 9(01) VALUE ZERO. *** FILE STATUS VARIABLES *** 05 WS- FILESTATUS. 10 WS-CMSTR-FST PIC 9(02) VALUE ZEROES. 10 WS-CTAB-FST PIC 9(02) VALUE ZEROES. *** END OF FILE VARIABLES *** 05 WS-CMSTR-EOF PIC X(01) VALUE 'N'. 88 WS-CMSTR-EOF-YES VALUE 'Y'. 88 WS-CMSTR-EOF-NO VALUE 'N'. 05 WS-CTAB-EOF PIC X(01) VALUE 'N'. 88 WS-CTAB-EOF-YES VALUE 'Y'. 88 WS-CTAB-EOF-NO VALUE 'N'. **** ERROR VARIABLES **** 05 WC-ABEND-900 PIC 9(03) VALUE 900. 05 WE-ERR-CODE PIC 9(02) VALUE ZEROES. 05 WE-ABEND-CODE PIC 9(03) VALUE ZEROES. ************************************************************ **** ********* PROCEDURE DIVISON ********** ************************************************************ **** PROCEDURE DIVISION. 0000- BEGIN. PERFORM 1000-INITIALISE THRU 1000- EXIT. PERFORM 2000-PROCESS THRU 2000- EXIT UNTIL WS-CMSTR-EOF- YES. DISPLAY 'WS-CMF-RECS-REWRITTEN :' WS-CMF-RECS- REWRITTEN. PERFORM 5000-CLOSE THRU 5000- EXIT. GOBACK. 0000- EXIT. EXIT. 1000- INITIALISE. OPEN I-O CMSTR. EVALUATE WS-CMSTR- FST WHEN 00 WHEN 97 CONTINUE WHEN OTHER DISPLAY 'ERROR IN READING INPUT FILE: ' DISPLAY WS-CMSTR-FST MOVE WS-CMSTR-FST TO WE-ERR-CODE PERFORM 9999-ABEND-PARA THRU 9999-EXIT END-EVALUATE. OPEN INPUT CTAB. EVALUATE WS-CTAB-FST WHEN 00 WHEN 97 CONTINUE WHEN OTHER DISPLAY 'ERROR IN READING INPUT FILE: ' DISPLAY WS-CTAB-FST MOVE WS-CTAB-FST TO WE-ERR-CODE PERFORM 9999-ABEND-PARA THRU 9999-EXIT END-EVALUATE. 1000-EXIT. EXIT. 2000-PROCESS. READ CMSTR. EVALUATE WS-CMSTR-FST WHEN 00 CONTINUE WHEN 10 SET WS-CMSTR-EOF-YES TO TRUE GO TO 2000-EXIT WHEN OTHER DISPLAY 'ERROR IN READING INPUT FILE: ' DISPLAY WS-CMSTR-FST MOVE WS-CMSTR-FST TO WE-ERR-CODE PERFORM 9999-ABEND-PARA THRU 9999-EXIT END-EVALUATE IF CM2-RECORD-TYPE-SOLD-TO MOVE CM2-ENTERING-BRANCH TO WS-EB PERFORM 3000-READ THRU 3000-EXIT UNTIL WS-CTAB-EOF-YES END-IF. 2000-EXIT. EXIT. 3000-READ. MOVE WS-EB TO VSAM-WHSE-CD. MOVE 'WHSE' TO VSAM-WHSE-ID. READ CTAB. EVALUATE WS-CTAB-FST WHEN 00 MOVE WHSE-DIV-CODE TO WS-DIV PERFORM 4000-REWRITE-CMF THRU 4000-EXIT WHEN 10 SET WS-CTAB-EOF-YES TO TRUE GO TO 3000-EXIT WHEN OTHER DISPLAY 'ERROR IN READING TABLE FILE: ' DISPLAY WS-CTAB-FST MOVE WS-CTAB-FST TO WE-ERR-CODE PERFORM 9999-ABEND-PARA THRU 9999-EXIT END- EVALUATE. 3000- EXIT. EXIT. 4000-REWRITE- CMF. IF WS-DIV = 250 OR 252 MOVE 'F' TO CM2-FREIGHT- TYPE MOVE 1 TO CM2-FREIGHT-THRESHOLD- AMT ADD +1 TO WS-CMF-RECS- REWRITTEN REWRITE CM2-SOLD-TO- RECORD DISPLAY 'RECORD UPDATED' END- IF. * EVALUATE WS-CMSTR- FST * WHEN 00 * CONTINUE * WHEN OTHER * DISPLAY 'FILE NOT UPDATED' * DISPLAY WS-CMSTR- FST * MOVE WS-CMSTR-FST TO WE-ERR-CODE * PERFORM 9999-ABEND-PARA THRU 9999-EXIT * GO TO 4000-EXIT * END-EVALUATE. 4000-EXIT. EXIT. 5000-CLOSE. CLOSE CMSTR CTAB. 5000-EXIT. EXIT. 9999-ABEND-PARA. COMPUTE WE-ABEND-CODE = WC-ABEND-900 + WE-ERR-CODE CALL 'ILBOABN0' USING WE-ABEND-CODE GO TO 5000-CLOSE. 9999-EXIT. EXIT. 5000-CLOSE. CLOSE CMSTR CTAB. 5000-EXIT. EXIT. 9999-ABEND-PARA. COMPUTE WE-ABEND-CODE = WC-ABEND-900 + WE-ERR-CODE CALL 'ILBOABN0' USING WE-ABEND-CODE GO TO 5000-CLOSE. 9999-EXIT. EXIT. //this program is giving maxcc=0, but not updating..
I have File 1 occurs 5 times with Employee-ID,Employee-Name,Employee-Dept (EEE and MECH). I have File 2 occurs 10 times with Employee-ID,Employee-Name,Employee-Dept (EEE,CIVIL,CHEMICAL and MECH). In FIle 1 and FIle 2 , for matching Employee-DEPT (Only MECH) , we need to move entire records from file1 to file 2. We should not use 2D array. Your help is needed here.
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