Re: Resiliency To New Data Requirements

From: Neo <neo55592_at_hotmail.com>
Date: 5 Aug 2006 13:30:47 -0700
Message-ID: <1154809847.309911.33710_at_i42g2000cwa.googlegroups.com>

> What exactly do new, select, create, update, delete do?

Something similar to what create, select, insert, update and delete do in RMDBs. Documentation for various functions is available via www.dbfordummies.com/NLI/function.asp

For example the following dbd and SQL psuedo scripts are roughly equivalent:

(new)
(create person instance (it))
(create (it) name (word+ 'john))
(create (it) age (val+ '28))

INSERT INTO T_Person (
                    (SELECT wordID FROM T_Word WHERE string = "john"),
                    (SELECT ageID FROM T_Age WHERE value = 28));

Assuming CREATE TABLE T_Person (auto personID, nameID, ageID);

> What kind of scope do symbols have?

I don't understand your question. I am familiar with the concept of a variable having a scope within a block, a function, a module and an application. In dbd, symbols are modelled the same as John and Mary. What scope do John and Mary have in RMDBs?

> > The expression for the word john is ...
>
> I couldn't really follow this.

In dbd, the following are different things: string john, word john and person john. Various expressions specify each and the relationship between them. Received on Sat Aug 05 2006 - 22:30:47 CEST