题解 | 统计所有课程参加培训人次
统计所有课程参加培训人次
https://www.nowcoder.com/practice/98aad5807cf34a3b960cc8a70ce03f53
SELECT
SUM(CASE WHEN course LIKE '%course1%' THEN 1 ELSE 0 END) +
SUM(CASE WHEN course LIKE '%course2%' THEN 1 ELSE 0 END) +
SUM(CASE WHEN course LIKE '%course3%' THEN 1 ELSE 0 END) AS staff_nums
FROM
cultivate_tb;
CASE WHEN
