Re: catch table changes

["Joe Sam Shirah" <jshirah@xxxxxxxxxxxxx>]

    Hi Csaba,

    The responders so far have given you the two ways to "catch" live
database changes.  I understand that you said "Doing this work with triggers
is unacceptable", for reasons we don't quite understand, but either triggers
or invoking from the journal should give acceptable results; far better than
polling.  The primary concern is to have them do as little work as possible.

    We have some apps that use triggers, including watching for inserts,
without problems.  OTOH, I'm aware of a group that used triggers extensively
and managed to kill throughput because they tried to do so much with them.
The triggers were in RPG, so there was no language issue.

> Unfortunatelly, the traditional host languages, like
> COBOL, RPB is difficult to start learning.

    RPB on the '400 is especially difficult.    ;-P   That's a joke, in case
no one got it.

    Seriously, if you have no "traditional" programmers on staff, you should
be able to find someone to do it for you.  Certainly there are people
available on this list who could do it easily.  Polling ( in almost all
cases ) is the least attractive and most resource consumptive choice.


                                                  Joe Sam

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----- Original Message -----
From: "Csaba Kabai" <cskabai@xxxxxxxxxxx>
To: <java400-l@xxxxxxxxxxxx>
Sent: Monday, March 29, 2004 8:16 AM
Subject: Re: catch table changes


>
> >If you could give us a little more information about what you are trying
> to
> >accomplish, we can probably give you better answers.
>
> Dear Chris,
>
> In summary, what i want to solve:
>
> I try to accomplish that if on the AS400/DB2 table has changed,
> (INSERT, UPDATE, DELETE) these events publicated to
> a DATAQUEUE. On the other side of the queue there
> is a Java program which is receiving the information.
> Based on these entries,  another database tables (MSSQL) be
> inserted, updated, deleted.
> Doing this work with triggers is unacceptable, because if there is a
> trigger on the table, other file manipulations are delimited.
> At the present time, i can read/write the queue with java
> to propagate the changes, but can't catch the table change
> event (maybe signal?), only to frequently query the tables.
>
> I know, that there is a great solutions for the problem, such as
> DataPropagator, Host Integration Server etc, but we are
> thinking of a 'cheaper' way. :(
>
> I see, the problem is not as simple as the first sight.
> Unfortunatelly, the traditional host languages, like
> COBOL, RPB is difficult to start learning. Java has opened the
> "black box" for me, but not wide enough.
>
> Thanks,
> Csaba Kabai