On Sat, Jun 20, 2026 at 5:51 AM Peter Duffy <peter@???> wrote:
>
> One thing which has been going through my mind about this subject is
> that the process has already happened in the evolution of database
> systems.
>
> In the beginning was the hierarchical database - all the data arranged
> in a tree so that each item of data had a single parent. Blindingly
> fast, but complex to maintain, and inflexible. I think that IBM's IMS
> is the only surviving example - but it's still widely used.
>
> Then came network databases - extend the hierarchical model so that a
> node can have more than one parent. Increases the flexibility whilst
> maintaining the speed of access - but enormously increases the
> complexity and maintenance. Difficult to find any extant examples: the
> model was developed by the CODASYL task group in the late 1960s, and
> the main result was IDMS.
>
> Then Edward Codd developed the relational database model: any data item
> could be related to any other by a shared attribute/value. Infinitely
> flexible - but so resource-heavy that at first it was thought to be
> impractical. However, with the rapid development of faster hardware,
> this was found not to be the case, and now the relational database has
> eclipsed the previous database types, to the point that one hardly ever
> hears about them.
>
> ISTM that what we're thinking towards is an analogue of the relational
> database applied to files. With extended attributes and metadata, we're
> effectively at the "network database model" stage. So the question
> would appear to be: how to replicate the evolution of the relational
> model from the network one in terms of files and filesystems. (And -
> it's such an obvious thought-thread that it seems self-evident that it
> must have already been done by someone somewhere.)
>
> One of the best summaries of the database models that I've yet seen is
> on the MariaDB site: three articles, one each for the three models,
> starting with this one:
>
> https://mariadb.com/docs/general-resources/database-theory/understanding-the-hierarchical-database-model
>
>
Very interesting - - - with followup articles also of interest - - - thank you!!

Regards