Re: Record Lock

There is one program that generates the check number. It is a simple RPG
that chains the file by company only, adds 1 to the existing number and
places this on the screen for the user.

I have put in a chain right there to ensure that this new number does not
already exist, and I have also added a log file to this program.

There is also another program that does checks which I am checking now but
I beleive it only calls the first program.

I was told that for checks, they don't indicate the division ever, only
company.

I still want to know what happens to the file lock, when a term. freezes.

Thank you,

Steve

Now I have found out, that someone here thinks it occurs when the users
terminal gets LOCKED. But first of all, wouldn't a record lock remain in
effect or would the CL program that holds the lock in effect deallocate
this lock? yet the check number started to change, did change? its a bit
confusing, but it makes some possible sense.

Record locks have nothing at all to do with the creation of the check
number.  Furthermore, _object_ locks (ALCOBJ) have nothing to do with
the contents of any particular record.  It's hard to tell what you mean
by 'terminal gets locked.'  Sounds like a program failure of some sort.

 > I am looking at a situation that occassionaly
 > occurs, that a check number is allowed to be
 > entered that is a dup.

 > the key is CO, Div, batch#, check#,
 > so you could have the same number and a diff batch.

If the key is Co, Div, Batch, Check, then the database designer is
explicitly allowing for duplicate check numbers, as long as they occur
in a different company or division or batch.

 > Or to put it another way, how would you
 > design such a program in such a
 > way that a dup could NEVER happen?

My choice would be to create a new logical file keyed by check number,
unique.  That way the database enforces your business rule (no duplicate
check numbers.)  However, as Lim warns, this could ripple through the
application, causing problems you don't want if there are already
'duplicate' check numbers in the file.

As Jerry asked, where do these check numbers come from?  Does the
application generate them, or are they input from somewhere (like a
customer payment batch?)  If your application generates the check
number, there are two tried and true mechanisms for guaranteeing a
unique number.  Data area and control file.

*lock in dtaara    // locks dtaara; nobody else can read
add 1 check
out dtaara

'check' chain ctlfile   // locks record; nobody else can chain
add 1 check
update ctlfile

   --buck
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