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Paul Popiel writes:
> is there anyway of placing a key constraint on an optional attribute?
That's what 'unique' constraints are for -- not required to be
present, but required to be unique _when_ present.
If that's not what you meant, more details of your document type and
requirements are needed. . .
ht
- --
Henry S. Thompson, HCRC Language Technology Group, University of Edinburgh
Half-time member of W3C Team
2 Buccleuch Place, Edinburgh EH8 9LW, SCOTLAND -- (44) 131 650-4440
Fax: (44) 131 650-4587, e-mail: ht@inf.ed.ac.uk
URL: http://www.ltg.ed.ac.uk/~ht/
[mail really from me _always_ has this .sig -- mail without it is forged spam]
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