MySql常用操作SQL语句汇总_MySQL
MySQL的常见操作在这里先做一下总结,已经整合到代码里面,经过检验无误。
代码如下:
/*创建一个数据库*/
create database xuning_test;
/*说明当时使用数据库对象*/
use xuning_test;
/*向数据库中添加表并且定义表的结构*/
create table person(
id int not null,
name varchar(16) not null,
sex varchar(16) not null,
age int not null,
address varchar(128) not null,
remark varchar(512) not null
);
/*向数据库的表中插入数据*/
insert into person value
(1,'name_1','men',99,'beijing','This is a frindsheep boy'),
(2,'name_2','men',88,'shanghai','ok great'),
(1,'name_3','man',77,'guangzhou','This is lickly'),
(1,'name_4','men',66,'beijing','This is a frindsheep boy'),
(1,'name_5','men',55,'beijing','you dont going to shool'),
(1,'name_6','man',44,'beijing','This is a frindsheep boy'),
(1,'name_7','men',33,'beijing','This is a frindsheep boy'),
(1,'name_8','man',22,'beijing',''),
(1,'name_9','men',11,'beijing','This is a frindsheep boy')
;
/*查询时否成功插入*/
select * from person;
/*下面是多种查询方式*/
/*根据列的名称属性值*/
select name from person;
/*添加条件-根据性别*/
select name from person where sex = 'men';
/*也可以用比较符作为条件--一定逗号隔开*/
select name,address from person where age > 50;
/*看做对象去使用数据库和表的关系=---双表关联--对象关系一定要明确*/
select xuning_test.person.name, xuning_test.person.id, xuning_test.person.age, xuning_test.person.address
from xuning_test.person, test1.test_xuning
where xuning_test.person.id = test1.test_xuning.id
;
/*使用表的别名进行查询*/
use xuning_test;
select c.name,sex from person as c where c.age > 40 and c.address='beijing';

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