database/votable data types

[Mark Taylor]

Hi DAL (Pat?),

I have a question about the intent of the table in sec 2.5 of TAP 1.0,
which associates VOTable datatypes with database column types.

The associated text says

   "The default mapping of data types are shown [in the table]"

but I'm not quite sure what "default" means in that case.

My concrete question/example is this:

   If a column declares itself with datatype VARCHAR in TAP_SCHEMA.columns,
   is it REQUIRED to appear with datatype="char" in the VOTable output
   of a query response?

The reason this has come up is because Markus has some VARCHAR columns
which appear as unicodeChar in VOTable output.  This is a reasonable
thing to want to do, but I don't know if it's legal.  If not, this
should be another item to address for future evolution of TAP;
though it might get addressed in future evolution of VOTable if that
happens.

Mark

--
Mark Taylor   Astronomical Programmer   Physics, Bristol University, UK
m.b.taylor at bris.ac.uk +44-117-9288776  http://www.star.bris.ac.uk/~mbt/