Re: Ada DB bindings and APQ

[Brian May <bam@snoopy.apana.org.au>]

>>>>> "Dmitry" == Dmitry A Kazakov <mailbox@dmitry-kazakov.de> writes:

    Dmitry> That's not OO, yet. It is rather typed vs untyped.

It seems to me it has all the features of an OO system (encapsulation,
abstraction, inheritance, etc). Rather the issue is that some design
decisions have been made that you don't agree with.

While I can see your point of view in issues such as the query type
being independent of the query string, I can also understand the
reasons behind doing it this way, and probably would have done the
same thing myself.

As far I can tell some of your goals of abstraction, while ideal,
solutions may require more thought and research in order to make sure
compatibility with all databases and to ensure your goals really are
met. For instance, my ideal abstraction layer would completely hide
the SQL layer completely but maintain the flexibility of the SQL
layer. This I think would be really difficult to do, and I am not
volunteering... It would mean that it could potentially work with any
database, not just an SQL based database.

Ok, back on planet Earth now, my sane and reasonable priorities for
this project would be:

1. Factory for creating a connection based on a URL (see my previous
   message). I would be happy to start working on this if desired
   (note: I don't claim to be any expert on parsing strings in
   Ada...).

   (note: with 1 completed the next step some people will demand is
   plugins so you can support other database without recompilation.  I
   personally don't think this is worth it at the moment, especially
   as APQ doesn't hide all differences in different databases).

2. Support for different character sets. I do not know what this would
   require, but it is a real problem that different database can have
   different character sets, and making assumptions isn't a good
   idea. Not only that, but in latest versions of mysql different
   tables within the same database can have different character
   sets. At the minimum I guess it should be possible to query what
   character set a table is encoded with (note: I don't know how to do
   this). 16 bit UTF support would be nice, but we have UTF8 in the
   meantime.

3. Support for other SQL based databases. Note I have this as the
   lowest priority...
-- 
Brian May <bam@snoopy.apana.org.au>