Robert Haas <robertmhaas@gmail.com> writes:
> On Tue, Sep 16, 2025 at 12:56 AM David G. Johnston
> <david.g.johnston@gmail.com> wrote:
>> If there are no function names present, output “expr” in lieu of a function name. Then just output any columns that
arepresent. No operators, no constants.
> In the previous discussion, the user's expression indexes were on
> these expressions:
> jsondata -> 'a' -> 'b'
> jsondata -> 'x' -> 'y'
> So "no operators, no constants" wouldn't really allow us to make any
> useful progress, inasmuch as it would throw away everything that
> matters.
Precisely. It's exactly expression indexes on OpExprs that
FigureColumn is completely useless for; if we don't do something
for those then we've not moved the needle much. I initially
tried leaving out Consts, but that didn't work well on the
indexes in the regression tests, let alone the field example
Robert cites.
One thing I was thinking about after putting up the initial draft
was to suppress the underscores around operator names, so that
instead of
mytab_jsondata_->_a_->_b_idx
the above would net you
mytab_jsondata->a->b_idx
It's less consistent but looks less busy too.
> I am not really sure we want to do what Tom proposes here because, as
> Pavel says, it would result in a lot of indexes containing special
> characters in the name.
Question is, why should we care about that?
regards, tom lane
