一道sql面试题(查询语句) id name age 1 a 11 2 b 11 3 c 12 4 d 13 5 e 12 . . . 查询age唯一的那一个 这个应该怎么写 满意答案 热心问友 2010-10-14 select * from table1 where id not in (select age from table1 group by age having count(1)>1) --Up…
SQL语句如下: select country, sum(case when type='A' then money end) as A, sum(case when type='B' then money end) as B, sum(case when type='C' then money end) as C from table1 group by country 本文转自:https://blog.csdn.net/Eastmount/article/details/50559008…
sql是测试从业者必备的技能之一,基本上也是笔试必考内容. 所以,不要让sql拖了后腿,有些测友一遇到多表关联查询就犯晕,甚至连单表的执行顺序都没搞懂,下面简单介绍下,顺便给一些题供大家练习. 单表执行顺序 select distinct 字段1,...,字段n from 库.表 where 条件 group by 分组字段 having 过滤 order by 排序字段 limit n; 执行顺序 from where group by having select distinct order…