Re: query that Bob is descendant of Alice

Robert Vazan wrote.
> I think SQL can express only static depth of links:

Hi Robert,

No, this is not true, but you need a lot of SQL experience to construct something decent.

> If databases cannot, I would like to see algorithm or
> something else, that helps.

How about playing with object databases? They typically can handle objects and descendants.

> 1. Can this be done? (practically)

Anything can be done.
It is only a matter of effort.

I have no idea about your exact query requirements. Maybe we are brainstorming through a similar area. We are working no a specification for an object-oriented query API here: http://www.odbms.org/soda/

Feel free to dicuss any points with us at: http://groups.yahoo.com/group/oodb

Kind regards,
Carl

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Carl Rosenberger
db4o - database for objects - http://www.db4o.com