At 12:15 AM 08-02-01 +0100, you wrote:

>Hi list.
>
>I'm getting AV when using
>
>if (Field.FieldName = 'XX') then begin ...
>
>in OnDataChange because Field = nil.

Why do you think Field = nil? The OnDataChange event passes a TIB_Column
variable called Field each time there is a data change in a row (note any
change, not just a modification).

>Is there any way to know which particular field that is changed and
>triggering the event?

Don't go this route - you are looking for a modified column in a row, not a
datachange event.

>When field XX is changed I wan't to update SQLWhere to filter a
>"lookup"-Query that is connected with keysource to another query.

Use the AfterPost event; or, better still, use DMLCaching to synchronize
the datasets.

>Maybe one should use params instead? If so, is there any difference in
>performance?

Difference in performance from what? Params are used everywhere...

Regards,
Helen

All for Open and Open for All
InterBase Developer Initiative · http://www.interbase2000.org
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