[orm-devel] The NUMERIC problem float-ing around (no more!)

Diedrich Vorberg orm-devel@mailman.tux4web.de
Sat, 7 Dec 2002 05:41:24 +0100


Good evening Eric!
Hi Ross, Julio and Mike! You guys still up?
A good afternoon Uwe!
And to those Europeans who got an early start or didn't bother to go 
sleep: a very good morning to you!

It's 5 A.M. now and I think it was worth it ;-)

This is how it works:

  o PostgreSQL returns its results SQL literals contained in strings
  o psycopg parses these strings and makes them Python objects
  o to do so it employs a well designed and very pythonesqe (same 
    thing really) mechanism 
  o the conversion of NUMERIC(sql) to float(py) is just a default and
    can be changed
  o I modified the pgsql.datasource so that it does just that. Now
    pgsql will return strings(py) for each SQL datatype that enherits 
    from orm.adapters.pgsql.column.customType
  o orm's convert()/format() mechanism takes care of converting these
    strings to the right Python objects now
  o I've created a numeric datatype and a numericColumn. They use the
    FixedPoint module you can find at

       http://fixedpoint.sourceforge.net/html/lib/module-FixedPoint.html

    This lets you use arbitrary precision/exact math just like pgsql 
    does internally.

The best thing about it: I didn't have to mess up the code :-)

Check out the new version from CVS and, if time permits, do some 
testing!

As you can plainly see, I'm having a great time working with you and 
I really dig this Free Software thing now. I liked the idea before, 
but now I dig it ;-)

Diedrich
-- 
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