Re: EXPLAIN (ANALYZE, BUFFERS) - puzzling numbers for a simple query.

On Sat, 2021-06-05 at 00:12 +1200, David Rowley wrote:
> As for the call to generate_series, you're not likely to ever get any
> great estimation from that.  The number of rows returned by a call to
> that particular function are just whatever is set in pg_proc.prorows,
> in this case, 1000.  The other generate_series functions which take
> INT and BIGINT inputs do have a prosupport function.

"generate_series" has a support function from v12 on:

EXPLAIN SELECT * FROM generate_series(1, 25);
                             QUERY PLAN                              
═════════════════════════════════════════════════════════════════════
 Function Scan on generate_series  (cost=0.00..0.25 rows=25 width=4)
(1 row)

Yours,
Laurenz Albe
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