Re: psql tab completion for DO blocks

On Sat, Jan 2, 2010 at 7:47 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Peter Eisentraut <peter_e(at)gmx(dot)net> writes:
>> On lör, 2010-01-02 at 17:34 -0500, Tom Lane wrote:
>>> As for the overhead, these queries are not zero-maintenance.  I still
>>> think that the usefulness of tab completion here is pretty darn
>>> minimal,
>>> since most people are more likely to rely on default_do_language;
>
>> We really don't have any data on that, and it doesn't seem all that
>> likely to me.
>
> I'm not really objecting to putting in the patch entirely.  I'm objecting
> to carrying an extra completion query for it.  I don't think hiding
> languages with laninline=0 improves its usefulness at all, let alone
> enough to justify extra maintenance burden.

As a practical matter there aren't that many languages in the first
place, and many of them begin with the same few letters. If you have
both plperl and plpython loaded (and they both have inline handlers)
you'll have to type four characters to disambiguate, and by that time
(especially for plperl) you might as well just finish typing it by
hand.

Having said that, I don't see much value in deliberately making the
tab-completion list fail to match the set of arguments that will
actually work. The maintenance burden of an additional query strikes
me as not worth worrying about. If David finds it useful and/or has
users who want it, I think we should just do it.

...Robert