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- -- 解法一
- SELECT
- t1.teacher_no,
- (CASE WEEK WHEN '1' THEN keshu ELSE 0 END ) 礼拜一,
- (CASE WEEK WHEN '2' THEN keshu ELSE 0 END ) 礼拜二,
- (CASE WEEK WHEN '3' THEN keshu ELSE 0 END ) 礼拜三
- FROM
- (
- SELECT
- teacher_no,
- WEEK,
- COUNT(1) AS keshu
- FROM teach
- GROUP BY teacher_no,WEEK
- )t1
- GROUP BY t1.teacher_no;
-
-
- -- 解法二 就是count()函数作用
- SELECT
- t1.teacher_no,
- (CASE WEEK WHEN '1' THEN keshu ELSE 0 END ) 礼拜一,
- (CASE WEEK WHEN '2' THEN keshu ELSE 0 END ) 礼拜二,
- (CASE WEEK WHEN '3' THEN keshu ELSE 0 END ) 礼拜三
- FROM
- (
- SELECT
- t.teacher_no,
- t.WEEK,
- COUNT(t.keshu) AS keshu
- FROM
- (
- SELECT
- teacher_no,
- WEEK,
- '1' keshu
- FROM teach )t
- GROUP BY teacher_no,WEEK
- )t1
- GROUP BY t1.teacher_no
- ;
网站题目：(一)、根据teacher_no统计星期的上课数-创新互联
标题链接：
http://cdkjz.cn/article/cojsgp.html
