select distinct SalaryasSecondHighestSalary from Employee order by Salary desc limit1,1; 然后去执行语句的时候,发现与预期结果相同,心里窃喜,这就算出来了。。。 代码语言:javascript 复制 输入:{"headers":{"Employee":["Id","Salary"]},"rows":{"Employee":[[1,100],[2,200],[3,300]]}}输出:{"...
SELECT( (SELECTDISTINCTSalary # distinct不能漏掉,排除重复值FROMEmployeeORDERBYSalaryDESCLIMIT1OFFSET1) )ASSecondHighestSalary limit/offset语法: 1. offset X是跳过X个数据,limit Y是选取Y个数据 2. limit X,Y中表示跳过X个数据,读取Y个数据 有些同学可能会疑惑,为什么要写两个select,不直接使用一个select...
这将根据评论员和电影对评论进行划分，然后根据最高的评分对评分进行排序。所以一个评审员可以评审多部...
select max(Salary) from Employee; # 2、求小于最大的值 select max(Salary) as SecondHighestSalary from Employee where Salary < (select max(Salary) from Employee); 1. 2. 3. 4. 5. 6. 7. 第二个思路,先将所有值倒序排,然后输出第二个就行 select Salary as SecondHighestSalary from Employee ...
因为窗口函数是 对where或者group by子句 处理后的结果进行操作,所以窗口函数原则上只能写在select子句中。 1.知识点总结: sum(...A...) over(partition by ...B... order by ...C... rows between ...D1 and ...D2...) avg(...A ... ) over(partition by ...B... order by ...C....
select * from 表名 group by 列名; 会根据指定的列名出现的不同的值进行分组 实测SQL会先执行筛选(where) 再执行分组( group by) 并且写代码时要先写筛选再写分组 否则会报错 实例1:根据指定的列的值对全表数据进行分组 然后列出每个组的第一条数据 ...
select * from employees where hire_date = (select max(hire_date) from employees); 1. 2. 3. 4. 5. 6. 7. 推荐优先使用子查询,因为如果最大的同时有N个,子查询可以全部查询到,但排序只能排一个 口试: 如果我只需要知道该字段的最值的具体value,那我直接select max from table即可,当然order by ...
SQL - maxvalue.sql Select the Nth Highest value from a table select level, max(col_name) from my_table where level = &n connect by prior (col_name) col_name)group by level;Example:Given a table called emp with the following columns:-- id number-- name .
order by对 salary进行排序,desc表示降序排列 # 然后是取第二个,limit 1 offset 1,是从下标1开始取一个数 # 然后利用子查询进行null判断,如果不是null,则为子查询结果,否则为null SELECT IFNULL( (SELECT DISTINCT Salary FROM Employee ORDER BY Salary DESC LIMIT 1 OFFSET 1), NULL) AS SecondHighest...
This lock blocks any attempt to insert, update, or delete any row with a key value that falls in the range because those operations would first have to acquire a lock on the index. For example, a SERIALIZABLE transaction could issue a SELECT statement that reads al...