Re: New function normal_rand_array function to contrib/tablefunc.

Hi,

> If we are going to add such a function to core, then I think we should
> make it consistent and at least as flexible as the other array
> functions, and support multi-dimensional arrays with optional
> non-default lower-bounds, like array_fill(). I.e., something like:
>
> random_array(min int, max int, dims int[] [, lbounds int[]]) -> int[]
>
> Returns an array filled with random values in the range min <= x <= max,
> having dimensions of the lengths specified by dims. The optional lbounds
> argument supplies lower-bound values for each dimension (which default
> to all 1).

FWIW we have several array_* functions that deal only with the first
dimension of an array: array_shuffle(), array_sample() the recently
added array_reverse() [1], the currently discussed array_sort() [2].

I suggest implementing the function in several steps. First implement
random_array(min, max, len). It's straightforward and IMO will provide
the most value to the majority of the users.Then we can either add an
optional argument or a random_array_multidim() function. This can be
implemented and discussed as a separate patch. This approach would be
convenient for the author and the reviewers and also will allow us to
deliver value to the users sooner.

[1]: https://git.postgresql.org/gitweb/?p=postgresql.git;a=commitdiff;h=49d6c7d8daba
[2]: https://commitfest.postgresql.org/50/5277/

--
Best regards,
Aleksander Alekseev