Subject Re: [IBO] IBO 4.2 Gc with D3 and Report Builder
Author Helen Borrie (TeamIBO)
At 02:20 AM 08-04-02 +0000, Andre wrote:

>I'm sorry, I made a mistake. I just want to tell that I'm using
>the "iboTDataset" - components. Of course I'm using the TIBOQuery!
>... there is no IBX at D3 at all ...

Good point. :))

Your problem (restated):
> I have a problem with TIBOQuery, Report Builder 4.x and Delphi 3.
> When I start the programm everything works fine. I'm able to scroll,
> insert, modify... Then I print the Report. Fine. But after it I can't
> do anything. It causes an Access Violation everytime. IBO 3 works
> fine!

Are you using IBO 4 with Delphi 3? which version/patch level?

Lester or Geoff will be able to guide you re compatibility of RB 4 with IBO
4.x but perhaps I can throw a glimmer of light on the Delphi side...

If you are getting an AV, it's because your application is trying to access
a de-referenced object somewhere. What are you doing to the IBOQuery when
the report completes? What does the Delphi trace monitor show?

An example of where an object could get de-referenced would be where your
query got closed, the transaction got committed, and then your application
tried to refer to a column or parameter in the query; or it tried to
commit (or post + commit, if you have Autocommit true on your IBODatabase)
a transaction that no longer exists.

If ReportBuilder isn't causing this condition, I'd want to go to the place
where your application enables editing of the query and insert code that
tests whether a transaction exists.
...
if not MyIBODatabase.TransactionIsActive then
...

You could also put an IB_MonitorDialog on your form and watch it until the
moment when the AV occurs.

It can also be a good idea to isolate the report task from the data entry
task. Add a TIBOTransaction for the report, with an isolation of
tiConcurrency, along with a TIBOQuery just for the report data. You can
pass across the currently selected data from your main query using the
InternalDataset.AssignSQLWithSearch method of this dedicated report dataset.

Without more detail, it's hard to offer any explicit help...


regards,
Helen Borrie (TeamIBO Support)

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