When I run the following two queries on the SmartForm Racing Database, I get the table of results below. Why doesn't all_weather = 1 for race_type = 'All Weather Flat'? Is one of these fields more reliable than the other or is there some other reason why an 'All Weather Flat' race would have all_weather != 1.
SELECT a.race_id
INTO
#sample_races
FROM
(SELECT *
FROM
historic_races
WHERE
course IN ('Kempton', 'Lingfield', 'Southwell', 'Wolverhampton')
AND distance_yards BETWEEN 5 * 220 AND 12 * 220
) a
INNER JOIN historic_runners b
ON a.race_id = b.race_id
GROUP BY
a.race_id
HAVING
min(b.age) >= 0;
SELECT course
, race_type
, all_weather
, count(b.race_id)
FROM
historic_races a
INNER JOIN #sample_races b
ON a.race_id = b.race_id
GROUP BY
course
, race_type
, all_weather
ORDER BY
course
, race_type
, all_weather;
course, race_type, all_weather, count(*)
Kempton All Weather Flat 0 223
Kempton All Weather Flat 1 1842
Kempton Flat 0 234
Kempton Flat 1 21
Lingfield All Weather Flat 0 247
Lingfield All Weather Flat 1 3574
Lingfield Flat 0 507
Lingfield Flat 1 53
Southwell All Weather Flat NULL 1
Southwell All Weather Flat 0 1336
Southwell All Weather Flat 1 1453
Southwell Flat 0 84
Southwell Flat 1 17
Wolverhampton All Weather Flat NULL 5
Wolverhampton All Weather Flat 0 441
Wolverhampton All Weather Flat 1 3711
Wolverhampton Flat 0 10
Wolverhampton Flat 1 11
