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Re: why hierarchy?

From: Neo <neo55592_at_hotmail.com>
Date: 26 Jul 2006 12:51:03 -0700
Message-ID: <1153943463.324708.168580@m73g2000cwd.googlegroups.com>


> From the link, apparently 'new', 'createWRR' and 'create' are functions ...

Yes, these are "functions" similar to CREATE, INSERT, SELECT, DELETE and UPDATE in SQL/RM.

> ... although it seems to talk only of syntax.

Yes, kind of like a car manual: Turn steering wheel to turn car. It doesn't explain how it is accomplished.

> What other functions are defined

The basic ones are create, select, update and delete. Others listed at www.dbfordummies.com/NLI/Function.asp

> and is the word function used in the usual sense?

Yes, see www.dbfordummies.com/NLI/Expression.asp

> Are you merely talking about alternative notation for LISP and a way to serialize it?

No, dbd is an implemenation of a data model that I developed. Dbd's scripting interface has LISP-like syntax. See www.dbfordummies.com/NLI/Default.asp

> For example, what analogue does it have to make a logical inference,
> such as 'these are the grand-nephews/first cousins twice removed of
> god's father's sisters'?

In the current universe/god/john/mary example, they are:

(; Find eve's children)
(; Finds john and mary)
(select eve child *)

(; Find john's parents)

(; Finds adam and eve)
(select john parent *)
(; Find adam's children that are part of mars)
(; Finds john)
(and (select adam child *)
     (select mars part *))

(; Find eve's children that are part of a planet)
(; Finds john and mary)
(and (select eve child *)

     (select (select planet instance *) part *))

(; Find god's grandchildren that are part of a planet)
(; Finds john and mary)
(and (select (select god child *) child *)
     (select (select planet instance *) part *))


Examples of more complex queries are at
www.dbfordummies.com/Example/Ex039.asp Received on Wed Jul 26 2006 - 14:51:03 CDT

Original text of this message

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