Thank you for your kind advice.
As you said that it is important to distiguish object data from document
data.
I am thinking how we can build document data base with XML. These data base
would have capability of full text search(as you said)
and of managing parts of a document, and of configuring document parts into
a document. If it has API for XML(SGML) Editors it would be better.
But I could not find such a data base which we can use casually. (All are
very very expensive!!)
Kenji