两种用法 一样, 查询字段类型需要一致 union 会自动去重 union all 不会去重 select name ,age from student union select name ,age from student2 相关文章: 2021-12-15 2022-12-23 2021-08-11 2022-01-09 2022-12-23 2022-12-23 2021-04-25 2022-02-03