[Dachs-support] TAP only catalogue

[Markus Demleitner]

Hi Yannick,

On Tue, Apr 19, 2022 at 02:00:42PM +0200, Yannick Roehlly wrote:
> Le mardi 19 avril 2022, 10:26:12 CEST Markus Demleitner a écrit :
> > But I give you the current behaviour doesn't feel right; I suppose I
> > never noticed it because I'm avoiding booleans where I can anyway
> > (and that's because ADQL can't do them and adding them to ADQL is a
> > huge pain).
> 
> What do you mean by “ADQL can't do them”? Do you mean as a proper Boolean?
> 
> In ADQL, I can't do `select * from schema.catalogue where flag` (which is 
> valid in SQL if flag is a Boolean) but I can do `select * from 
> schema.catalogue where flag = 'True'` (which works in SQL too, at least with 
> PostgreSQL).

Yes, that's what bothers me.  I think flag = 'True' does not buy
anything over flag = 1, but it breaks with the tradition established
by quite a few pseudo-boolean functions in ADQL (CONTAINS,
ivo_hashlist_has...).

> Well, your code snippets does not work as this because of the `<values 
> default="None">`; DaCHS complains that:

Oops; that was a lame experiment to perhaps trick DaCHS into
checking the ANY option by default.  Apologies.  I should have read
the code or at least removed the junk before pasting.

> I think it's worth an entry in the howDoI.

After the interop I'll touch the messy DaCHS/nevow formal code that
decides on checking the default option, and then I'll probably
add an howDoI entry and see how it goes from there.

> Maybe a better default behaviour who be to produce a select box with an empty 
> entry selected by default for ANY, then one entry for True, and for False.

Hm... not sure I prefer a select box... at this point I'm rather
convinced this is a classic for a radio button, if only there were an
obvious option to pop them all out (without javascript).  Hm.

Thanks,

           Markus