[Schevo-devel] Re: [EVALUATION] - How to Evolve a Database

[Matthew Scott]

Ilias Lazaridis wrote:
>> For early development where you want maximum flexibility I recommend
>> taking full advantage of the ability to specify initial and sample
>> values within your schema and using that schema to create a new database
>> each time you change your schema.  This approach has worked well for me.
> 
> This one has a low usability.

What is your criteria for determining usability?  At first glance, that
is an extremely relative statement you made :)

The usability of Schevo's initial and sample value mechanism is actually
pretty high, compared to alternative methods of doing so (such as
writing a separate script to manually perform Create transactions and
the like).

In all of the Schevo schemata that I've worked on in a "collaborative
first draft" situation -- where I am putting together a schema with a
non-programmer providing continuous input into the process -- the sample
value mechanism in Schevo has proven to be both unobtrusive and
extremely valuable for rapid initial schema development.

So, based on a few of those experiences, I will respectfully, but
nevertheless fully, disagree with the notion that Schevo's initial and
sample value mechanism has "low usability".


> An quick workaround would be to add a command "evolve", which is
> essentially an alias to "create" (nobody knows that).
> 
> evo db evolve database (or a similar term for "evolve")
> 
> http://dev.orbtech.com/schevo/ticket/34

A straight alias of "evolve" to "create" would not lessen confusion,
IMHO, and may not be compatible with the way the "evolve" command will
eventually be used.

I added a commment to this ticket regarding a create/update/evolve
proposal.


-- 
Matthew Scott
Springfield Technology