Re: array_to_set functions

On Wed, 2007-08-01 at 07:14 +0530, Merlin Moncure wrote:
> On 8/1/07, Decibel! <decibel@decibel.org> wrote:
> > David Fetter and I just came up with these, perhaps others will find
> > them useful:
> >
> > CREATE OR REPLACE FUNCTION array_to_set(anyarray, int) RETURNS SETOF anyelement LANGUAGE SQL AS $$
> >     SELECT $1[i] from generate_series(array_lower($1, $2), array_upper($1, $2)) i
> > $$;
> > CREATE OR REPLACE FUNCTION array_to_set(anyarray) RETURNS SETOF anyelement LANGUAGE SQL AS $$
> >     SELECT array_to_set($1, 1)
> > $$;
>
> very nice, although IMO there is a strong justification for these
> functions to be in core and written in C for efficiency (along with
> array_accum, which I have hand burn from copying and pasting out of
> the documentation).
>
> merlin
>
Excellent timing guys. :^)

I was trying to build a function to list the items of an array, but
ran into problems and was going to post what I had been working on.

Your functions work great.

In case you don't have the function to generate an array from a set
here is one I have been using :


CREATE AGGREGATE array_accum (
    BASETYPE = anyelement,
    SFUNC = array_append,
    STYPE = anyarray,
    INITCOND = '{}'
);


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