mysql - sql分组时选择行

Question

id | field_1 | field_2
1  | a       | 1
2  | b       | 1

SELECT id, field_1 FROM table GROUP BY field_2

这将获取 id = 1 的行，如何获取具有最大 id 的行？ (我想得到 field_1 = b)。实现此目标的最简单方法是什么？

感谢您的帮助!

Answer 1

SELECT t1.id, t1.field_1, t2.IdSum
FROM table t1
INNER JOIN
(
  SELECT field_2, MAX(id) id, SUM(id) IdSum
  FROM  Table
  GROUP BY field_2
) t2  on t1.id = t2.id
     AND t1.field_2 = t2.field_2;