Associating a shape with another shape as its datasource

It was pointed out to me that there is a use case for defining that a table
(that could be in an embedded spreadsheet, or in a text document)
is the data source for a chart.
Imagine a text document with an embedded spreadsheet and another embedded
object which is a chart (the chart is NOT inside the spreadsheet).
Is there already a way to say "this table is the data source for the chart"?
I didn't find a way, so I would like to request one.

My idea would be a new attribute chart:data-source-table-name whose value would be the table:name
of the table (whether it comes from text content or from office:spreadsheet)...
Hmm, this assumes table names are unique, which brings back a recent discussion
to mind about unique ids... iirc we decided that page names would be enforced to be unique,
right? So we could do the same with table names --- except that if they appear to
the user then we need a display-name :-)

-- 
David Faure, , sponsored by Trolltech to work on KDE,
Konqueror (http://www.konqueror.org), and KOffice (http://www.koffice.org).