Subject Possible Incorrect Logic in TIB_LookupCombo
Author Eric Handbury
Hello,

(BCB6-SP2, IBO-4.2Hf, FB-1.0, Enh2.1.2)

I have a LookupCombo, which when I hit 'DEL' to delete the entry in
the control, it sets the underlying field to NULL. I don't think this
is correct... I feel it should set the field to the value stored in
the DefaultValues.
What's happening with me is that I hit 'DEL' and it sets the field
value to NULL, then the 'FIELDXX is a required field' exception is
being generated. So to circumvent this I am checking the field value
in the BeforePost to see if it is NULL, and if so, setting it to 0
(my IB field attributes is INTEGER DEFAULT 0 NOT NULL). I shouldn't
have to do this on every BeforePost that has a LookupCombo... IBO
should really do it (since it knows what its default value is.)

Unfortunately, I don't have Delphi so changing the underlying code
is difficult but the current logic for the assignment is below:

procedure SysUpdateKeyLinksData (IBA_Dataset.IMP)
...
if tmpCanModifyKeyLinkField then
KeyDataset.FieldByName( KeyLinks.IndexValues[ ii ] ).Assign(
FieldByName( KeyLinks.IndexNames[ ii ] ));
...