Subject Re: [IBO] strange intermitent Access Violation errors likely due to a conversion issue?
Author m. Th.
bwc3068 wrote:
> 1) in my BDE application, I used wwQuery. I did NOT install and use IPIBODataset.pas to get and use wwIBOQuery. instead, I use IBOQuery's. should i switch them all to wwIBOQuery? would that matter for the SQL itself (ie. it doesn't make it to the grid before it AVs out)

No. IBOQuery runs just fine.

> 2) i do a lot of
> select p.*, l.* from MdPartL P, LinksMP L
> where P.uniqueKey = L.partUniqueKey
> and
> L.ModelUniqueKey = :UniqueKey
> it reads like that is a total no-no with FB2.1 and IBO 4.8.7. Would that not being a proper "join" syntax, would that cause an AV Error everytime or just once in a while?

It shouldn't. If you must change the above is because of performance

> 3) i do have persistent fields in persistent queries in my datamodule...sounds like for the few queries that are in the functions that are AV erroring, I should delete the fields and re-add them. I will do this.

From where you know which are "the functions that are AV erroring"?

> 4) the KeyLink property...i don't explicity set it. would that cause AV errors all the time or could it be just once in a while for the exact same SQL? i should set those too....
Not related.

> i use Firebird-

Good. Stable thing.

> I will explore more and look forward to any suggestions!

0. Be sure to ask the clear steps to reproduce the AVs. (From your
message I understand that you already did it, but without much success.
Don't worry. You're not alone. But, anyway is good to have the steps).

1. Can you tell the users the following?

"Guys, when that AV appears, with the dialog open, press Ctrl+C. After
this open your text editor of choice (Notepad, Wordpad, Word etc.) and
do a Ctrl+V there. Then Save & eMail that error message".

...and after this post that AVs here.

2. Install at least JCL ( on your
dev machine (if you aren't already). JCL comes with an Exception Dialog
wizard (see File | New...) which also does logging, error eMailing &
stack tracking (if you'll configure correctly). Embed this in your
application & give it to your users. With JCL's Exception Dialog soon
you'll have a bunch of stack trace logs to analyze. If you still
encounter problems please post the logs here.

NOTE: I gave you the JCL solution because is free and works very very
very well. But if you have another commercial exception handler in your
app (madExcept, EurekaLog etc.) then please feel free to post the Stacks
here as well as steps.


m. th.