Re: File locking / field locking

Hi Doug
The lock is on the record you have just READ and NOT the record you want to
add.
It is still feasible for another process to read the same files as
input/add, read the same record that you have just locked, and add the same
record you want to add, thus creating duplicates.
The best way around this is to make the file unique on that field and by
using monitor, to capture the error of attempting to create a duplicate
record



Alan Shore
Programmer/Analyst, Direct Response
E:AShore@xxxxxxxxxxx
P:(631) 244-2000 ext. 5019
C:(631) 880-8640
"If you're going through Hell, keep going" - Winston Churchill

rpg400-l-bounces@xxxxxxxxxxxx wrote on 10/17/2008 09:56:39 AM:

I have two files SourcePF is my physical file and SourceLF is a

logical

built over that PF. Both are included in the program as update files

with

add.

In a subroutine the program sets a HIVAL on the logical and then does

a

readp in order to get the highest shipping number. At this point I
believe this field is locked and no other process can access read that
record. it then increrments the count and writes it to a variable.

The

other variables are setup and then the program finally writes a new

record

to the Physical file, which at that point the lock is released

correct?

I am just checking every possible place for this thing to create

duplicate

records (I did not write the code, just plugging the hole).....and

making

sure that neither program can dup up the same number.
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Thank you.
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