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Thanks for the memory prompt and yes I do seem to recall doing that - -
It has been 45 + years ago :(
Vince
On 23/09/2019 12:06, Joe Monk [email protected] [H390-MVS] wrote:
> "Delete Option. In order to keep the number of records in the overflow
> area to a minimum, and to eliminate unnecessary records, an existing
> record may be marked for deletion. This is done by moving the
> figurative constant HIGH-VALUE into the first character position of
> the record. The record is not physically deleted unless it is forced
> off its prime track by the insertion of a new record (see "Using the
> WRITE Statement" in "Accessing an Indexed File Randomly"), or if the
> file is reorganized. Records marked for deletion may be replaced
> (using BISAM) by new records containing equivalent keys. Execution of
> the READ statement in QISAM does not make available a record marked
> for deletion, whether the record has, been physically deleted or 'not."
>
> Joe
>
> On Sun, Sep 22, 2019 at 8:18 PM Vince Coen [email protected]
> <mailto:[email protected]> [H390-MVS] <[email protected]
> <mailto:[email protected]>> wrote:
>
> Well I have been programming in Cobol since around 1964/5 from IBM
> 1401,7094, ICL1900's,IBM360s and yes a lot more after the 60's
> and I do
> not recall using anything other than DELETE having move the record
> key in.
>
> Now I cannot say it was the same for the 1401/7094 as I do not have a
> manual to hand but 360 and 1900 yes.
>
> The idea of use high-values into the key I have never seen but there
> again my memory may be playing tricks and I am only 72.
>
> Vince
>
> On 20/09/2019 19:51, [email protected]
> <mailto:[email protected]> [H390-MVS] wrote:
> > Many thanks, that's a very useful post (and very nostalgic!).
> >
> > I played around with some of the examples, and got them working
> with
> > little trouble. The main difference, as far as I can see,
> between your
> > manual and the COBOL MVT compiler that we have on the turnkey
> system,
> > is in the way that ISAM records are deleted.
> >
> > Your manual uses a DELETE statement, that I've never seen before. I
> > did it the more traditional way, by putting HIGH-VALUE in the
> > DELETE-KEY field and then doing a REWRITE. Worked fine, it's the
> way I
> > remember from about 1967 or thereabouts.I guess things have
> moved on
> > since then.
>