目前我有这个
SELECT
COUNT (enrollment_id) AS enrollments,
COUNT (result) AS
MAX (result) AS highest_result,
AVG (result) AS average_result,
MIN (period_code) AS earliest_enrollment
FROM
enrollment
WHERE
result IS NULL
我想要的是总的注册人数,这COUNT(enrollment_id)
是为了什么。然后我想计算NULL
结果列中的值的数量以获得unfinalised_enrollments
.
WHERE
底部的子句会影响SELECT
使用结果列的其他语句吗?如果是这样,我该怎么做才能只NULL
计算结果列中值的数量并将其显示在名为unfinalised_enrollment
.
提前致谢。