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 round( sum( course_num ),0 ) staff_nums FROM ( SELECT ( CHAR_LENGTH( course ) + 1 ) / 8 course_num FROM cultivate_tb WHERE course IS NOT NULL ) t
