Re: Relational Database vs. Nonrelational

[Elna Tymes <etymes -at- LTS -dot- COM>]

Colleen -
>
> Can anyone out there give me information on differences between a
> relational database vs. nonrelational?

Think of the difference between data on a tape (linear) and data on a
disk (non-linear, usually).  The older, linear databases used files that
started with some header descriptor, then associated data in a series of
fields.  Within a set, all records had the same fields, regardless of
whether they had data.

With relational databases, fields can be used in a number of ways (and
can be of variable length), provided that they are linked in tables.
Rather than looking up the field in each record, you request data in a
named field in a named table.   Where the data happens to be stored is
pretty much irrelevant.

With object-oriented databases, you again are not limited by the size or
physical location of the field, but in addition your fields can have
inheritance.  In other words, if you're working with an airline
scheduling program, for instance, the field "Crew" can inherit the
characteristics of the type of plane - you'll need fewer people for some
kinds of planes than for others.

There are LOTS of other differences, but that's a snapshot.

Elna Tymes
Los Trancos Systems