At 02:42 PM 20/08/2003 -0700, you wrote:

>Does a TIB_Query support persistent fields?

No.

> If not, is there a reasons?

Under the hood, the architecture of native IBO is completely different to
the VCL data access. Every "data item" that comes from the database
(fields[]) or is passed to the database (params[]) is a
TIB_Column. TIB_Columns are grouped into Row objects. IB_Column and
IB_Row objects get their internal data at prepare time. You'll find
multiple kinds of Row objects at work inside a dataset - as well as field
and param objects, you will find KeyFields, Old... objects, BufferFields,
et al. Once a dataset is prepared, you can refer to the properties of
unknown IB_Column objects through the Row, e.g. to update calculated
fields or to apply parameter values.

Rather than try to find "reasons" for the difference, browse the help for
TIB_Column and TIB_Row and look at their properties and methods. These are
the fundamental classes in native IBO and will give you a good perspective
on the breadth of the data attributes and run-time structures that IBO
manages.

As you have probably discovered already, the native IBO data-aware controls
are very different to the VCL. Behaviour of controls in the UI is driven
by attributes that are set on TIB_Column objects - in contrast to VCL
components, which take attributes that control how data objects behave in
the UI.

Helen