My problem is "solved" and I need a little help for base functions of IBQueries.
This way I found it.
I added a component "IBQuery_Margin1" and did the same with it.
This worked.
So WHAT!!, what is the difference?
I found it, if I right-clicked the IBQuery_Margin and said "edit fields" (in German = bearbeiten).
There I found listed: Margin and datum (=date) and NOT Ware.
"Ware" is the one which has been the prob lem all the time.
See screenshot.
Is there a way to give the beginner-user an error message, if this happens reading,
"you dummy have used the field editor and not added the field, you request now"
or
Do anything from programmer-side, that the field-editor fields do not "hide" fields?
or
Do not allow to use those field-edited-queries any more for other queries?
(this is tricky as it may block code, which worked for years)