1 、创建数据库
#语法：
CREATE DATABASE dbName;
#创建数据库rms
create database rms;
2、切换数据库
#选择数据库
USE dbName;
#选择数据库rms;
use rms;
3、 查看所有的数据库名称
SHOW DATABASES;
4、创建表
#语法：
#columnName：字段名称
#columnType：字段类型
CREATE TABLE tableName(columnName,columnTypei);
#创建表customers
CREATE TABLE `customers` (
`customerNumber` int(11) NOT NULL,
`customerName` varchar(50) NOT NULL,
`contactLastName` varchar(50) NOT NULL,
`contactFirstName` varchar(50) NOT NULL,
`phone` varchar(50) NOT NULL
) ;
5、查看数据库中所有的表
SHOW TABLES;
6、查看表结构
#语法：
DESC tableName;
#查看customes的结构
DESC customers;
mysql> DESC customers;
+------------------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------+-------------+------+-----+---------+-------+
| customerNumber | int(11) | NO | | NULL | |
| customerName | varchar(50) | NO | | NULL | |
| contactLastName | varchar(50) | NO | | NULL | |
| contactFirstName | varchar(50) | NO | | NULL | |
| phone | varchar(50) | NO | | NULL | |
+------------------+-------------+------+-----+---------+-------+
5 rows in set (0.03 sec)
7、插入数据
#语法：
INSERT INTO tableName(columnName1,columnName2,columnName N)values(value1,value2,valueN);
#columeName也可以不写
INSERT INTO tableName values(value1,value2,valueN);
INSERT INTO customers(customerNumber,customerName,contactLastName,contactFirstName,phone)values(001,"Stephen Wang",'Stephen','Wang','15687965432');
INSERT INTO customers(customerNumber,customerName,contactLastName,contactFirstName,phone)values(003,"Lucy Liu",'Lucy','Liu','15687965432');
8、查看表中的数据
#语法：
SELECT * FROM tableName;
mysql> select * from customers; +----------------+--------------+-----------------+------------------+-------------+
| customerNumber | customerName | contactLastName | contactFirstName | phone |
+----------------+--------------+-----------------+------------------+-------------+
| 2 | Vicent Wang | Vicent | Wang | 15687965438 |
| 1 | Stephen Wang | Stephen | Wang | 15687965432 |
| 3 | Lucy Liu | Lucy | Liu | 15687965432 |
+----------------+--------------+-----------------+------------------+-------------+
3 rows in set (0.00 sec)
#查看表中的某些字段,语法：
SELECT columnName1,columnName2 from tableName;
mysql> select customerNumber,customerName from customers;
+----------------+--------------+
| customerNumber | customerName |
+----------------+--------------+
| 2 | Vicent Wang |
| 1 | Stephen Wang |
| 3 | Lucy Liu |
+----------------+--------------+
3 rows in set (0.00 sec)
#where条件
#查看客户编号为1的记录
mysql> select customerNumber,customerName from customers where customerNumber=1;
+----------------+--------------+
| customerNumber | customerName |
+----------------+--------------+
| 1 | Stephen Wang |
+----------------+--------------+
1 row in set (0.00 sec)
9、 更新数据
#语法：
UPDATE tableName SET columeName=value where conditions;
#将客户编号为1的客户手机号修改为15997654325
mysql> update customers set phone='15997654325' where customerNumber=1;
Query OK, 1 row affected (0.62 sec)
Rows matched: 1 Changed: 1 Warnings: 0
10、模糊查询
#语法：
select * from tableName where columnName like ''condition [and /or] [columeName = value];
#查询表里last name为Wang的客户
mysql> select * from customers where contactFirstName like '%wang';
+----------------+--------------+-----------------+------------------+-------------+
| customerNumber | customerName | contactLastName | contactFirstName | phone |
+----------------+--------------+-----------------+------------------+-------------+
| 2 | Vicent Wang | Vicent | Wang | 15687965438 |
| 1 | Stephen Wang | Stephen | Wang | 15997654325 |
+----------------+--------------+-----------------+------------------+-------------+
2 rows in set (0.08 sec)
11、排序与分组
排序语法：
select * from tableName order by columnName asc / desc;
#按照客户编号递增排序
mysql> select * from customers order by customerNumber asc;
+----------------+--------------+-----------------+------------------+-------------+
| customerNumber | customerName | contactLastName | contactFirstName | phone |
+----------------+--------------+-----------------+------------------+-------------+
| 1 | Stephen Wang | Stephen | Wang | 15997654325 |
| 2 | Vicent Wang | Vicent | Wang | 15687965438 |
| 3 | Lucy Liu | Lucy | Liu | 15687965432 |
+----------------+--------------+-----------------+------------------+-------------+
3 rows in set (0.00 sec)
#分组语法
#按照contactFirstName分组并统计客户个数
mysql> select contactFirstName,count(*) from customers group by contactFirstName;
+------------------+----------+
| contactFirstName | count(*) |
+------------------+----------+
| Liu | 1 |
| Wang | 2 |
+------------------+----------+
2 rows in set (0.03 sec)
12、修改字段名称
#新增字段语法：
alter table tableName add columnName;
#修改字段语法：
alter table tableName modify columnName;
#删除字段语法：
alter table tableName drop columnName;
#customers添加一个状态字段，类型为char(20)
mysql> alter table customers add staus char(20);
Query OK, 0 rows affected (0.78 sec)
Records: 0 Duplicates: 0 Warnings: 0
mysql> select * from customers;
+----------------+--------------+-----------------+------------------+-------------+-------+
| customerNumber | customerName | contactLastName | contactFirstName | phone | staus |
+----------------+--------------+-----------------+------------------+-------------+-------+
| 2 | Vicent Wang | Vicent | Wang | 15687965438 | NULL |
| 1 | Stephen Wang | Stephen | Wang | 15997654325 | NULL |
| 3 | Lucy Liu | Lucy | Liu | 15687965432 | NULL |
+----------------+--------------+-----------------+------------------+-------------+-------+
3 rows in set (0.00 sec)
13.、删除
#删除表中的记录,语法：
delete from tableName where conditions;
mysql> delete from customers where customerNumber=1;
Query OK, 1 row affected (0.06 sec
#删除表数据和结构，语法：
drop table tableName;
mysql> drop table customers;
Query OK, 0 rows affected (0.16 sec)
#删除数据库,语法：
drop database dbName;
mysql> drop database rms;
Query OK, 0 rows affected (0.13 sec)