Re: Whither 1:1?

On Fri, Jun 1, 2018 at 9:52 AM, Guyren Howe <guyren(at)gmail(dot)com> wrote:

> It’s come to my attention that what seems an obvious and useful database
> design pattern — 1:1 relations between tables by having a shared primary
> key — is hardly discussed or used.
>
> It would seem to be a very simple pattern, and useful to avoid storing
> nulls or for groups of fields that tend to be used together.
>
> Thoughts? Is there some downside I can’t see?
>

​I make considerable use of one-to-one tables. There isn't any inherent
absolute downside to doing this that I can think of (potentially more joins
are neither inherent ​nor absolute) though the specific benefits or
concerns rely upon the specific model being implemented.

The two ways I've done this is "static vs dynamic data" split and,
basically, "attribute grouping". This is one that can avoid storing nulls
though in my particular usage I still have them since I'm basically
implementing a key-value json document and so have a record for the ID in
every table even if no data is present. The advantage is reducing model
complexity by adding meta-data to all of the fields contained fields.

David J.

>