这道题可以用自联结来解决,解决思路就是,找到id大1且num相等以及id号大2且num相等的num,具体SQL如下: SELECTDISTINCTlog1.NumAS'ConsecutiveNums'FROMLogslog1INNERJOINLogslog2ON(log2.Id=log1.Id+1ANDlog2.Num=log1.Num)INNERJOINLogslog3ON(log3.Id=log1.Id+2ANDlog3.Num=log1.Num); 626.Exchange...
FROM-on->WHERE->GROUPBY-> HAVING ->SELECT的字段 ->DISTINCT->ORDERBY-> LIMIT 例如: SELECTDISTINCTplayer_id, player_name,count(*) as num# 顺序 5FROM playerJOINteam ON player.team_id = team.team_id# 顺序 1WHERE height >1.80# 顺序 2GROUPBYplayer.team_id# 顺序 3HAVING num >2# 顺序 4...
selecttoday.idfromWeatherasyestdayleftjoinWeatherastodayondatediff(yestday.recordDate,today.recordDate)=-1wheretoday.Temperature>yestday.Temperature; 1661. 每台机器的进程平均运行时间 原题:https://leetcode.cn/problems/average-time-of-process-per-machine/ 题意:现在有一个工厂网站由几台机器运行,每台...
com/problems/consecutive-numbers/solution/lian-xu-chu-xian-de-shu-zi-by-leetcode/ 6 超过经理收入的员工 left join 除了= 还可以> 我 Select Name as Employee from (select p.*,q.sALARY AS MANAGERsalary from Employee p left join Employee q ON p.MANAGERid = q.ID) t where sALARY > MANAGER...
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链接:https://leetcode.cn/problems/all-the-pairs-with-the-maximum-number-of-common-followers #测试数据 Create table If Not ExistsRelations(user_id int,follower_id int);insert intoRelations(user_id,follower_id)values('1','3');insert intoRelations(user_id,follower_id)values('2','3');inser...
SQL INTERVIEW QUESTIONS AND ANSWERS 3 | P a g e 3.What is the difference between the “DELETE” and “TRUNCATE” commands? The DELETE command is used to remove rows from a table based on a WHERE condition whereas TRUNCATE removes all rows from a table. ...
Write a SQL query to find all customers who never order anything. Using the above tables as an example, return the following: 三、参考SQL 方法一:左外连接 1 select Name as Customers2 from Customers c3 left join Orders o4 on =o.CustomerId 5 where is null; 1. 2. 方法二:子查询(官方方...
sql编程算法 来源:力扣(LeetCode) 链接:https://leetcode-cn.com/problems/add-strings 著作权归领扣网络所有。商业转载请联系官方授权,非商业转载请注明出处。 Michael阿明 2020/07/13 1.6K0 LeetCode 43. 字符串相乘(大数乘法) 编程算法 给定两个以字符串形式表示的非负整数 num1 和 num2,返回 num1 和 nu...
https://leetcode-cn.com/problems/customers-who-never-order/ 📕解题思路 根据题目,我们先看题目要求我们查什么,要查出从不订购任何东西的顾客。根据这一点我们可以从Orders订单表中得知CustomerId为1和3的是订购过东西的顾客,而2和4则没有订购过任何东西。再从Customers顾客表中查id2与id4对应的顾客名字就查...