IBClientDataset and Provider Fields

When using this composite component, how do the ProviderFlags work in
conjunction with a Joied Query.=?

My query is at the bottom.

Firstly I am surprised that the provider was unable to resolve the table
name, and I had to provide the table name.

More importantly, despite changing the Provider Flag settings on the display
only fields (s.Ref, Subdepartment, and DepartmentName, the Provider is
always tryin g to update these columns.

Could someone advise how we are supposed to set the IBClientDataset so that
in a joined QUery the Update SQL will only use columns where the flag
pfInUpdate is set true.

Thanks,

Tony.

select P.*, S.Ref, S.Description SubDepartment, D.DepartmentName from Plu P

join Department D on D.DepartmentID = P.DepartmentID

join SubDepartment S on S.SubDepartmentID = P.SubdepartmentID

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