• To: "'Ken North'" <kennorth@s...>,<xml-dev@l...>
• Subject: RE: Designing XML to Support Information Evolution
• From: "Michael Kay" <michael.h.kay@n...>
• Date: Tue, 25 May 2004 12:04:34 +0100
• In-reply-to: <009701c44242$e7ad8540$1601a8c0@DURANTE>
• Thread-index: AcRCQrCFQr8+mQGkT9K+DwyinbPisQABBnyg

> 
> The network model from the CODASYL DBTG supports many-to-many 
> relationships but,
> like a hierarchical database, it's based on pointers.

No, the model is not based on pointers: this is a popular myth. It is the
implementations that were based on pointers. In 1970, one could not afford
the luxury of doing extra disc transfers just to make data reorganisation
easier. But it would be perfectly possible to design an implementation of
the network model that was optimised for evolution rather than being
optimised for speed of navigation.

Michael Kay

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