On Wed, Nov 11, 2020 at 5:56 PM Bruce Momjian <bruce@momjian.us> wrote:
On Thu, Nov 12, 2020 at 12:18:49AM +0000, Dagfinn Ilmari Mannsåker wrote: > Bruce Momjian <bruce@momjian.us> writes: > > I think we could do it, but it would only work if the column was output > > as a single json value, and not a multi-key/value field. I am afraid if > > we tried to do it, the result would be too inconsistent to be useful. > > Could this be done via the support function, so that the top-level > operator/function in each select list item can return a suggested column > name if the relevant arguments are constants?
Yes, the user explicitly calling a function would be much easier to predict.
For the user an operator and a function are different ways to invoke the same underlying thing using different syntax. I'm not seeing how this syntax difference makes this any easier to implement for explicit function invocation compared to operator function invocation.
