VSAM processing

    VSAM processing is basically reading different types of Files – ESDS,KSDS ,RRDS  using sequential ,random ,dynamic access .

•  In Cics as its in batch we have the same metods of access ,only difference is in the commands . 
•  Lats us comapre batch to CICS and see the simialrity ,and understand the concept better.
•  In batch if we have a partial key info available and we want to browse the same 

MOVE SPACES                     TO TRNM-KEY.

MOVE partial info               TO TRNM-KEY.
Ie
MOVE WS-IN-ACCT-CORP            TO TRNM-CORP.              
           MOVE WS-IN-ACCT-COMP            TO TRNM-COMP.
MOVE WS-IN-ACCT-MAJR            TO TRNM-MAJR.              
           MOVE WS-IN-ACCT-MINR            TO TRNM-MINR.

START IN-GLMATR-FILE KEY NOT < TRNM-KEY.

READ IN-GLMATR-FILE NEXT RECORD.


IF IN-GLMATR-EOF                                      
       MOVE 'Y'                     TO WS-GLMATR-END-OF-FILE
       GO TO 2100-900-EXIT                              
END-IF.                                            
                                                             
IF IN-GLMATR-ST = '00'                            
       IF WS-IN-ACCT-CORP = TRNM-CORP                  
       AND WS-IN-ACCT-COMP = TRNM-COMP              
  AND WS-IN-ACCT-MAJR = TRNM-MAJR              
         AND WS-IN-ACCT-MINR = TRNM-MINR              
           PERFORM 2105-SELECTED              
      ELSE                                                  
             MOVE 'Y'                TO WS-GLMATR-END-OF-FILE  
             GO TO 2100-900-EXIT                              
 END-IF      
END-IF.      


Note that when the basic key values passed itself don’t match ,we do an EOF forcibly to prevent further proccessing .


In case of CICS

EXEC CICS HANDLE CONDITION
018670          DISABLED(D510-NOT-AVAILABLE)
018680          DUPREC
018690          ENDFILE (D520-ENDFILE)
018700          NOSPACE
018710          NOTFND  (D515-NOT-FOUND)
018720          NOTOPEN (D510-NOT-AVAILABLE)
018730     END-EXEC.
018740

018750     EXEC CICS STARTBR
018760               FILE      ('FREQCLUB') -------à>> file name .

018770               KEYLENGTH (WS-GEN-KEY-LENGTH) ==è>> key size of the partial key being used .

018780               REQID     (WS-REQID)          =è>    
018790               RIDFLD    (RWF01-00-RECORD-KEY)
018800               GENERIC ==========================è only for ksds .indicates only part of the key should be used .

018810               GTEQ ============è  > or = to key


18820     END-EXEC.


Then we use

EXEC CICS READNEXT
019380               FILE   ('FREQCLUB')
019390               INTO   (WS-IN-FREQ-FILE)
019400               LENGTH (WS-FILE-LENGTH)
019410               REQID  (WS-REQID)
019420               RIDFLD (RWF01-00-RECORD-KEY)
019430     END-EXEC.
019440

EXEC CICS ENDBR
020390          FILE ('FREQCLUB')
020400     END-EXEC.

This is to eplicitly end the browse operation  .

For update of the file we will use

000591      EXEC CICS READ
000592           FILE('WPRD010')
000593           INTO(WS-PROM-SHIPPER-REC)
000594           RIDFLD(AI-RECKEY)
000595           UPDATE
000601           RESP(RESPONSE-CODE)
000596      END-EXEC.
000597
000586      EVALUATE TRUE
000587        WHEN RESPONSE-CODE = DFHRESP(NORMAL)
000588             CONTINUE
000592        WHEN OTHER
000593             EXEC CICS
000594                  ABEND
000595             END-EXEC
000596      END-EVALUATE.
000000
000598      EXEC CICS REWRITE
000599           FILE('WPRD010')
000600           FROM(PROMO-SHIPPER-FILE)
000601           RESP(RESPONSE-CODE)
000584      END-EXEC.

For write

00560      EXEC CICS WRITE
000561           FROM(PROMO-SHIPPER-FILE)
000562           RIDFLD (AI-RECKEY)
000563           DATASET('WPRD010')
000564           RESP(RESPONSE-CODE)
565 END-EXEC.

NOTE:-

IN the STARTBR coomand first we specify the key value in the RIDFLD .but once the command executes ,the value returned to this field is an identifier of the record got .