jiang_1603的博客

MySQL是流行的数据库系统，下面记录了在Ubuntu 16.04上安装mysql步骤。如果你使用的是Ubuntu 16.04以前的版本，可以看这里：Ubuntu 14.04/15.10升级到Ubuntu 16.04 LTS。一. 安装MySQL1. 安装前先更新软件包列表：$ sudo apt update112. 在Ubuntu 16.04上安装MySQL：$ su

刚安装完并且配置好，创建了个表，想增加个用户，结果一直都是这个问题，尝试了好多个密码都不行，，，直到百度我才想起来，在运行mysql_secure_installation这玩意的时候，密码强度我设置了１——medium(= =)，没想到中级密码都那么强，大小写字母+数字+符号...所以不得不修改这个设置了，因为我想设密码123456(hia hia)很简单，登录root后一句话，就能更改密码

176. Second Highest SalaryEasyWrite a SQL query to get the second highest salary from the Employee table.+----+--------+| Id | Salary |+----+--------+| 1 | 100 || 2 | 200 || 3 | 3...

180. Consecutive NumbersMediumSQL SchemaWrite a SQL query to find all numbers that appear at least three times consecutively.+----+-----+| Id | Num |+----+-----+| 1 | 1 || 2 | 1 ||...

184. Department Highest SalaryMediumSQL SchemaThe Employee table holds all employees. Every employee has an Id, a salary, and there is also a column for the department Id.+----+-------+------...

196. Delete Duplicate EmailsWrite a SQL query to delete all duplicate email entries in a table named Person, keeping only unique emails based on its smallest Id.+----+------------------+| Id | E...

题目描述查找入职员工时间排名倒数第三的员工所有信息CREATE TABLE `employees` (`emp_no` int(11) NOT NULL,`birth_date` date NOT NULL,`first_name` varchar(14) NOT NULL,`last_name` varchar(16) NOT NULL,`gender` char(1) NOT ...

The Employee table holds all employees. Every employee has an Id, and there is also a column for the department Id.+----+-------+--------+--------------+| Id | Name | Salary | DepartmentId |+---...