Re: Postgres chooses slow query plan from time to time

Hello Tomas,

The auto explain analyze caught this:

2021-09-14 06:55:33 UTC, pid=12345  db=mydb, usr=myuser, client=ip,
app=PostgreSQL JDBC Driver, line=55 LOG:  duration: 5934.165 ms  plan:
  Query Text: SELECT *   FROM myschema.mytable pbh WHERE
pbh.product_code = $1   AND pbh.cage_player_id = $2   AND
pbh.cage_code = $3   AND balance_type = $4   AND pbh.modified_time <
$5 ORDER BY pbh.modified_time DESC FETCH FIRST 1 ROWS ONLY
  Limit  (cost=0.70..6.27 rows=1 width=66) (actual
time=5934.154..5934.155 rows=1 loops=1)
    Buffers: shared hit=7623 read=18217
    ->  Index Scan Backward using mytable_idx2 on mytable pbh
(cost=0.70..21639.94 rows=3885 width=66) (actual
time=5934.153..5934.153 rows=1 loops=1)
          Index Cond: ((cage_code = $3) AND (cage_player_id = $2) AND
(modified_time < $5))

So it expected to get 3885 rows, but got just 1. So this is the
statistics issue, right?