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Help with an interesting Postgres question: Why isn't an Index Only Scan used on a partition accessed via the parent table?.
CREATE TABLE towns ("id" int)
INSERT INTO towns VALUEs (1),(2),(3)
3 rows affected
select format('%s - %s',min(id),max(id) )min_max_vals from towns;
| min_max_vals |
|---|
| 1 - 3 |
create function min_max_val( cols text,tables text)
returns SETOF RECORD
LANGUAGE plpgsql
AS $$
begin
RETURN QUERY EXECUTE 'select format(''%s - %s'',min('||$1||E'),max('||$1||E') ) AS min_max_vals from '||$2||E';';
end
$$ ;
SELECT min_max_vals
FROM
min_max_val('id','towns')
AS t( min_max_vals tEXT)
| min_max_vals |
|---|
| 1 - 3 |