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From: ballou@databs.enet.dec.com
Newsgroups: comp.object
Subject: Re: Updates on class taxonomy
Message-ID: <1991Jan16.101331@databs.enet.dec.com>
Date: 16 Jan 91 15:16:03 GMT
References: <1991Jan15.152723.3862@tukki.jyu.fi> <91Jan14.165013est.7093@neat.cs.toronto.edu>
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Reply-To: ballou@databs.enet.dec.com ()
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In article <1991Jan15.152723.3862@tukki.jyu.fi>, sakkinen@tukki.jyu.fi writes:
|> In article <91Jan14.165013est.7093@neat.cs.toronto.edu> vinay@cs.toronto.edu
writes:
|>  [...]
|>
|> >If the updates are required should they be on-line or off-line ?  
|> >How frequent are the updates ?  What are the good examples of such updates
?
|> >Should they be done one at a time or should be permmitted concurrently ?
|> 
|> Updating the definitions of classes while they have instances
|> continues to be a hard and important research problem for OO databases.

Two of the foundation papers in this area are:

      Banerjee, J., W. Kim, H.J. Kim, and H.F. Korth, "Semantics and
      Implementation of Schema Evolution in Object-Oriented Databases,"
      Proceedings of ACM SIGMOD, San Francisco, CA, May 1987.

      Penney, D.J. and J. Stein, "Class modification in the GemStone
      Object-Oriented DBMS," Proceedings of OOPSLA '87, Orlando, FL,
      October 1987.

Nat Ballou
DEC OODB