TAP RFC [MTIME]
patrick.dowler at nrc-cnrc.gc.ca
Thu Sep 17 10:22:34 PDT 2009
Now with my implementor hat on:
On Thursday 17 September 2009 09:32:31 Patrick Dowler wrote:
> Is it extraneous? Once PQL is defined, one could find this information by
> doing two requests: MAXREC=0&SELECT=ALL and MAXREC=0&SELECT=PRIMARY, for
although it technically works, this is pretty painful for something this
simple; it also does nothing for a smart adql client application that is
trying to help a user write queries for a service they are exploring.
> So, the first question is: should we just remove it as extraneous (at least
> in 1.0)?
> If we keep it, as purely a categorisation hint from the service provider,
> what do we change the column name in TAP_SCHEMA.columns to?
I think this is simple metadata that allows a service to better describe the
content. Smart applications will be able to use it in conjunction with any
query language to build default queries the user can tweak later on. It helps
solve the problem that real databases have a lot of columns that are needed
for specific things but will likely overwhelm someone new to that site.
Creating views are an option for the service provider, but then the namespace
has more database objects and realtionships between them that the users have
My vote is to keep the concept of primary column(s), but rename it so it is
not a pain to implement.
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