[TAP] Summary: data type for column metadata
seaman at noao.edu
Thu Apr 16 11:49:56 PDT 2009
Mark Taylor wrote:
> - I'd say TIMESTAMP as a char array using ISO-8601 format makes
> sense. But I may be prepared to retract that if Rob or Arnold bites
> my head off.
I've got nothing against a restricted subset of ISO-8601.
My earlier point was that "timestamp" is not an overarching concept
that applies to every possible timekeeping situation. Sometimes you
do indeed want an epoch, the concept which appears to most closely
correspond to the notion of a timestamp that has been tossed around in
Sometimes you want a calendar date. The lack of a time does not in
this case represent a 24 hour imprecision, rather today is 16 April
2009 all day long. The handling issues (e.g., localization and
logistics) may be different than with timestamps.
And sometimes you want a clock time, e.g., an expression of Earth
orientation, without a date.
The latter two cases can also be handled by ISO-8601 or sexagesimal or
floating point or even integers.
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