{d,f,m} | {"3, 4": 2550, "3, 6": 800, "4, 6": 1632, "3, 4, 6": 5000}

(1 row)

-- correctesimates

-- correctestimates

SELECT * FROM check_estimated_rows('SELECT COUNT(*) FROM ndistinct GROUP BY a, b');

estimated | actual

-----------+--------

WHEREs.stxrelid='ndistinct'::regclass

ANDd.stxoid=s.oid;

SELECT*FROM check_estimated_rows('SELECT COUNT(*) FROM ndistinct GROUP BY a, b');

SELECT*FROM check_estimated_rows('SELECT COUNT(*) FROM ndistinct GROUP BY a, b, c');