Subject clearing comboBox in grid does not produce NULL
Author scronkey
Hi there,

I have a problem, but I'm not sure if I'm missing something.

I have a master-detail form, with a lookupCombo tied to one of the
fields in the detail (using TIB_Grid)
This field is STK_ID.

I also have a before update trigger for the detail table, which
checks the value of STK_ID and performs various actions accordingly.

In the trigger, I have the code:
IF (new.STK_ID <> old.STK_ID) THEN

Now, if I change the value in the STK_ID combo, the trigger is
correctly fired. BUT if I clear the value in the combo (by hitting
DEL), the trigger is not fired.

I want the combobox to clear, and therefore set a value of NULL to
the underlying field, but this does not appear to be happening.

Is this a known problem, that when DEL is pressed on a lookup combo,
it is NOT setting the field to NULL?