[plt-scheme] schemeql

From: Francisco Solsona (solsona at acm.org)
Date: Tue Mar 25 19:57:57 EST 2003

"Anton van Straaten" <anton at appsolutions.com> writes:

>>  (a) to catch, inside SchemeQL, any exception regarding the use of
>>  col-attribute, ignore it, and then try col-attributes (note the
>>  final `s', which is the ODBC 2.0 name for the exact same function!)

[...]

I just want to let you know that I just committed some changes to do
(a) above to the SchemeQL @ schematics cvs repository.

I also added a bunch of changes to several files to handle exceptions
the Right Way(TM), i.e. schemeql-error is now a substruct of exn, and
hopefully you will see now the little red bug in DrScheme when
something goes wrong¹.

>> According to this reference I have, inverting the condition above is
>> not the Right Thing(TM) to do either.  It would mean that your ODBC
>> driver is 2.0 compliant, not 3.51, or such... but is it?
>
> I didn't think that inverting the condition would be a permanent or general
> fix, but it seems to have worked for this case (so far)...  perhaps the
> driver is simply sufficiently backwards compatible?

Yes, that it may be.  In any case, numbers like 3.51 in the error
messages these drivers send always confuse me, because I would
expect them to support col-attribute, and not col-attributeS, etc.

> Did you mean " *shoot* all ODBC creators"?  No argument from me!

Yes, sorry... :-{

> BTW, from the little I've done with it so far, SchemeQL looks very cool, not
> to mention useful.  It's also a great example of why it's useful to be able
> to embed languages.

*blush*... thanks, and the SCSH guys are porting² SchemeQL to SCSH, so
it will be even more useful, or so I hope.  Further more, some of the
schematics people is working on a set of _database layers_ to submit
as SRFIs, and SchemeQL (or something like it) will be the highest
level layer.

--Francisco

Footnotes: 
¹ SchemeQL still catches all of SrPersist's exceptions, and raises its
own exceptions, or sends appropriate messages when it is safe to do
so.

²  Of course, many of us will want to see scsh ported to plt too. :-)




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