Re: A new proof of the superiority of set oriented approaches: numerical/time serie linear interpolation

From: Jon Heggland <jon.heggland_at_idi.ntnu.no>
Date: Wed, 02 May 2007 12:18:23 +0200
Message-ID: <f19oki$v63$1_at_orkan.itea.ntnu.no>


Brian Selzer wrote:
> "Cimode" <cimode_at_hotmail.com> wrote in message
> news:1178044184.315215.167590_at_p77g2000hsh.googlegroups.com...

>> What is a *database value* ?  What do you mean that a database
>> (collection of facts) is one single value?  Do you mean a relation
>> value? (the database being perceived as one single complex relation?)
>>

>
> The term "database" is pretty loaded. Most of the time a database is a
> value, a set of relations conforming to a particular schema--a
> representation of a collection of facts at a particular instant. In the
> context of modification, on the other hand, a database is a mutable entity
> whose state transitions from value to value as a result of a series of
> events. I use the phrases "database value" and "database state" to
> forestall any confusion.
>
> A set is a value. A database (in the first sense) is a set of named sets
> (relations) of sets (tuples) of named values (attribute values) that
> conforms to a particular schema. Therefore it is a single value.

Or, if you want to simplify the above by avoiding "state" and "mutable", you could say (as D&D do) that a database is a variable---a dbvar---which has a db value. Which is a tuple.

-- 
Jon
Received on Wed May 02 2007 - 12:18:23 CEST

Original text of this message