DBNavigator.Refresh doesn't (refresh) ??

Hi people,

I have a DBNavigator controlling a  DBGrid which is the detail part of a
master-detail form.  Its datasource uses a Query dataset which  is just :
select * from  detail  where detail.custno = :"custno"
I can edit or add records OK but when I click on the refresh button I get
the error
"Table does not support this operation because it is not uniqely indexed"

The underlying table "detail" has a unique index defined on 2 columns.

Any ideas why this doesn't work?

--
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|  Craig Kinsman
|  Control Innovation
|  cra...@comsys.com.au
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