[SQLObject] partial fix for DateTimeCol and Postgres

[Bud P. B. <bu...@si...>]

Ian and all,

here is a partial fix for DateTimeCol and PostgreSQL.  The problem is
that DATETIME is not defined, but TIMESTAMP should be used.  

fix:

I changed the DateTime class in Col.py to the following:

---------------------------------------------
class DateTimeCol(Col):

  def _mysqlType(self):
    return 'DATETIME'
		       
  def _postgresType(self):
    return 'TIMESTAMP'
---------------------------------------------

After this, the following seems to work ok:

* creates tables with DateTimeCols correctly (I believe)

* new seems to work correctly and insert a timestamp value

* the DateTime attribute can be accessed and is of type DateTime


But I found at least one remaining problem:

* after assigning a different value to the DateTime attribute, it's
  type changes to string!!!

For details, I attach the test routine I used and its output.

Will try to get a BooleanCol working...

--b