将结果合并为一行

Question

如何在SQL中将这些结果显示在一行？

Answer 1

您可以使用GROUP BY执行此操作：

SELECT school_id, school_name, grade, SUM(CASE WHEN Gender='F' THEN 1 ELSE 0 END) as female, SUM(CASE WHEN Gender='M' THEN 1 ELSE 0 END) as male
FROM yourtable
GROUP BY school_id, school_name, grade;