Re: A Working document has been submitted

From: Clive Page <cgp-at-star.le.ac.uk>
Date: Tue, 7 Oct 2003 10:24:44 +0100 (BST)


I think there may be a typo in the IVOA Sky Node v0.5 document: in section 5 QI-6 the function 'degree' should I think be 'degrees' as that is the spelling in the SQL and JDBC standards (and matches the plurality of 'radians').

I have a question: to what extent are user define functions supported or permitted? I see that in QI-9 there is what looks like a REGION function, though it is described as a 'keyword'. The example given is

  Region ('CIRCLE J2000 19.5 -36.7 0.02')

This looks to me a lot like a function call, and would be a lot more flexible if it took a string arg and 3 numeric arguments. Is there a way of defining more functions (or keywords) - since we shall surely want more? Or can they be used in expressions and passed transparently to the SQL-speaking back-end, in roughly the way that JDBC does?

-- 
Clive Page
Dept of Physics & Astronomy,
University of Leicester,    Tel +44 116 252 3551
Leicester, LE1 7RH,  U.K.   Fax +44 116 252 3311
Received on 2003-10-07Z11:25:49