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库操作https://www.dnzp.com/uploads/allimg/240301/hadatuzzwlg> 创建数据库：create database shujuku创建带字符集的数据库：create database mydb2 CHARACTER SET=UTF8创建带校验的数据库：create database mydb3 CHARACTER SET=UTF8 COLLATE utf8_general_ci显示数据库：show databases删除数据库：drop database shujuku修改数据库编码：alter databaese shujuku character set gb2312

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表操作https://www.dnzp.com/uploads/allimg/240301/hadatuzzwlg>

创建数据库表（创建一个表名为：employee，该表中含有id、name、sex、birthday、job字段）；https://www.dnzp.com/uploads/allimg/240301/hadatuzzwlg>

create table employee(id int,name varchar(40),sex char(4),birthday date,job varchar(40),);https://www.dnzp.com/uploads/allimg/240301/hadatuzzwlg> 表中增加image字段：alter table employee add image blob修改job值，使其长度为60（原长度为1000）：alter table employee modify job varchar(60)删除sex列：alter table employee drop sex;表名改为user（原名为employee）：rename table employee to user修改表的字符集为utf_8:alter table user character set utf8列name修改为 username：alter table change columm name username varchar(100)删除表：drop table user

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增删改查实例https://www.dnzp.com/uploads/allimg/240301/hadatuzzwlg>

准备表：https://www.dnzp.com/uploads/allimg/240301/hadatuzzwlg>

create table employee(id int,name varchar(40),sex varchar(4),birthday date,entry_date date,salary decimal(8,2),resume text);https://www.dnzp.com/uploads/allimg/240301/hadatuzzwlg>

插入表数据：https://www.dnzp.com/uploads/allimg/240301/hadatuzzwlg>

insert into employee(id ,name,sex,birthday,entry_date,salary,resume) values(1,'zhangsan','male','1999-08-22','2020-08-22,'1000','i am a developer');https://www.dnzp.com/uploads/allimg/240301/hadatuzzwlg> 指定某些列插入数据：insert into employee(id) values(6)插入汉字：insert into employee(id,name) values(6,‘张三’)

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修改表数据https://www.dnzp.com/uploads/allimg/240301/hadatuzzwlg> 将所有员工薪水修改为5000元：update employee set salary=5000将姓名为’zs’的员工薪水修改为3000元：update employee set salary = 3000 where name=‘zhangsan’将姓名为’aaa’的员工薪水修改为4000元,job改为ccc：update employee set salary = 4000,job=‘ccc’ where name=‘张三’将wu的薪水在原有基础上增加1000元：update employee set salary = salary+1000 where name=‘张三’

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删除表数据https://www.dnzp.com/uploads/allimg/240301/hadatuzzwlg> 删除表中名称为“zs”的记录：delete from employee where job=‘ccc’删除表中所有记录：delete from employee使用truncate删除表中记录：truncate table employee

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查询表数据https://www.dnzp.com/uploads/allimg/240301/hadatuzzwlg> 查询表中所有学生的信息：select id,name,chinese,english,math from student查询表中所有学生的姓名和对应的英语成绩：select name,english from student查询姓名为wu的学生成绩：select * from student where name=‘张三’查询英语成绩大于90分的同学：select * from student where english>‘90’查询英语分数在 80－90之间的同学：select * from student where english>=80 and english=<90

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常见MySQL语句命令https://www.dnzp.com/uploads/allimg/240301/hadatuzzwlg> 进入mysql 命令行：mysql -uroot -p查看所有数据库：show databases创建数据库：create database niu charset utf8删除数据库：drop database niu选择数据库：use databases查看所有表：show tables查看创建数据库的语句：show create database databasename查看创建表的语句：show create table tablename查看表结构：desc tablenmae

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常见MySQL字段含义https://www.dnzp.com/uploads/allimg/240301/hadatuzzwlg> 自增长：auto_increment非空：not null默认值：default唯一：unique指定字符集：charset主键：primary key荐：【中国风动漫】除了《哪吒》，这些良心国产动画也应该被更多人知道！【中国风动漫】《雾山五行》大火，却很少人知道它的前身《岁城璃心》一个拿着十米大刀的男主夭折！声明来源：博客园，人工智能产业链联盟推荐阅读，不代表人工智能产业链联盟立场，转载请注明，如涉及作品版权问题，请联系我们删除或做相关处理！