Subject Re: [IBO] Problems with TwwIBOQuery and Params (Invalid Variant Operation - when opening detailquery)
Author Geoff Worboys

> I have to add, the value of the masterkey is 99990000000001!
> If the keyfield contains less digits it seems to work!
> > try to open the detail or master i get an "Invalid variant
> > Operation" message/exception.

The Variant datatype does not support INT64 (at least not directly).
I have come across this problem with other third party products that
expect to be able to store a field value in a variant.

TDataset and IBO force the storage of int64 into variant using a
special type indicator, but this vartype is not implemented for all
variant functions, sometimes leading to invalid operation errors.

In your instance you may be able to resolve the problem by splitting
your key values into multiple fields (IB and IBO supports compound

I would expect that the problem comes from the InfoPower code (since
IBO does not usually need to use variant for its manipulations). Do
you have the source for InfoPower, can you at least provide a
callstack for the problem. Perhaps someone else with InfoPower and
IBO full source can detect where the problem is coming from and a
workaround can be implemented.

One workaround may be to provide have int64 use string values with
AsVariant functions. But I have not tried this to see what happens.

Geoff Worboys
Telesis Computing