Re: Converting row elements into a arrays?

I'm used to the bog standard COUNT, AVG, MIN, MAX, SUM. It didn't occur to me that there would be others...

CREATE OR REPLACE FUNCTION agg_leftagg(l TEXT, r anyelement) returns text as
$$
BEGIN
  RETURN CASE
    WHEN l IS NOT NULL THEN  format('%s-%s', l, r)
    ELSE r::TEXT
  END;
END;
$$ LANGUAGE PLPGSQL;

CREATE AGGREGATE leftagg(anyelement) (SFUNC=agg_leftagg, STYPE=TEXT);

CREATE TEMP TABLE s AS SELECT generate_series(1,10) s;