I have three batch files which are running parallel and continuously namely proc1.bat, proc2.bat, proc3.bat calling three t3i files proc1.t3i, proc2.t3i, proc3.t3i
respectively as follows:


-****************************************************************************
-* Module name : proc1.t3i
-****************************************************************************
-*
%CONNECT
%BEGIN
EX proc1
%END
%DISCONNECT
%STOP_SERVER


-****************************************************************************
-* Module name : proc2.t3i
-****************************************************************************
-*
%CONNECT
%BEGIN
EX proc2
%END
%DISCONNECT
%STOP_SERVER


-****************************************************************************
-* Module name : proc3.t3i
-****************************************************************************
-*
%CONNECT
%BEGIN
EX proc3
%END
%DISCONNECT
%STOP_SERVER



In the ending of the above three fex files, I have used the same logic as shown below to insert a record in a common database STATUS.FOC:

$ File STATUS.MAS
FILENAME=STATUS, SUFFIX=XFOCUS , $
SEGMENT=STATUS_S1, SEGTYPE=S1, $
FIELDNAME=TID, ALIAS=TRANSID, USAGE=I9, FIELDTYPE=I, TITLE='TRANSID', $
FIELDNAME=TDATE, ALIAS=TRANS_DA, USAGE=YYMD, TITLE='TRANS_DA', $
FIELDNAME=TTIME, ALIAS=TRANS_TI, USAGE=I6L, TITLE='TRANS_TI', $


-****************************************************************************
-* Module name : proc1.fex
-****************************************************************************

......
......
......

TABLE FILE STATUS
BY HIGHEST 1 TID
ON TABLE SAVE
END
-RUN
-READ SAVE &TRANSID.I9.
-RUN

-SET &TRANSID = &TRANSID + 1;
-RUN

-SET &T_DATE = &YYMD;
-SET &N_TIME = EDIT(&TOD);
-SET &T_TIME = EDIT(N_TIME, '99$99$99');

SET COMMIT=OFF
-RUN

MODIFY FILE STATUS
INCLUDE
DATA
TID = &TRANSID,
TDATE = &T_DATE,
TTIME = &T_TIME,
END
-RUN

SET COMMIT=ON
-RUN

-****************************************************************************

The problem I am facing is that due to parallel running of the three batch files, I am getting same transaction id getting created for some records:

TRANSID TRANS_DA TRANS_TI
------- --------- --------
3165504 2012/09/01 054009
3165504 2012/09/01 054023
3165504 2012/09/01 054010

My primary key constraint is getting violated. Please help me where I am going wrong.

Please let me if there is a similar concept of oracle sequence in webfocus.

This message has been edited. Last edited by: Ahamed Thaha,

Without really checking the code...


...It think the

&READ &TRANSID

and

&TRANSID = &TRANSID + 1

Will do the trick to violate your primary key...
If these statement are not in the same transaction. Things can, and will go wrong.

Basic problem with any parallel processing. You can not read, increase and write without being sure another process doesn't do the same.

e.g. Nothing prevents this ( see below ) from happening.

Process1 Process2
READ             
         READ
IDX+
         IDX+1
         WRITE
WRITE

I don't work with maintain...
...but the help tells me "SET COMMIT = OFF" and "SET COMMIT = ON" will not do the trick anyway...

It should be something like

SET COMMIT = ON
...
...
-* Do whatever you have to do... 
...
...
COMMIT;
SET COMMIT = OFF

Then still, I don't know whether this is sufficient to solve the Read,Increment,Write trick...



But some Maintain wizard will correct me, I guess.

G'luck

If you have multiple processes updating a FOCUS file, it is imperative that the updates be done via SU (Simultaneous User option).

But, even with SU, you would still need to detect overlapping updates and revise the key accordingly. This should do it:

MODIFY FILE STATUS
FREEFORM TID TDATE TTIME
PERFORM P1
GOTO EXIT

CASE P1
MATCH TID
  ON MATCH COMPUTE
    TID=TID+1;
  ON MATCH GOTO P1
  ON NOMATCH INCLUDE
  ON NOMATCH GOTO ENDCASE
ENDCASE
DATA
TID = &TRANSID, TDATE = &T_DATE, TTIME = &T_TIME, $
END
-RUN

Note that SU requires a license.