mysql命令使用

#mysql登录方式

[root@b ~]# mysql -uroot -p　　　　　　　　　
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 6
Server version: 5.7.20 Source distribution

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Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql>

#查看全部的数据库

mysql> show databases;　　　　　　　　　　　　　　
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
+--------------------+
5 rows in set (0.00 sec)

#进入mysql数据库；

mysql> use mysql;　　　　　　　　　　　　　　　　
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed

#查看数据库里有多少张表

mysql> show tables;　　　　　　　　　　　　
+---------------------------+
| Tables_in_mysql |
+---------------------------+
| columns_priv |
| db |
| engine_cost |
| event |
| func |
| general_log |
| help_topic |
| innodb_table_stats |
| ndb_binlog_index |
| plugin |
| user |
+---------------------------+
11 rows in set (0.00 sec)

#建立名为lisi的数据库

mysql> create database lisi;　　　　　　　
Query OK, 1 row affected (0.06 sec)

#建立名为t1表，并建立两个字

mysql> create table t1 (id varchar(20),name varchar(20));　　　　
Query OK, 0 rows affected (0.08 sec)

#向表中插入数据

mysql> insert into t1 values("1","hello");　　　　　　　　　　
Query OK, 1 row affected (0.01 sec)

 

#查看t1表数据内容 

mysql> select * from t1;　　　　　　　　　　　　　
+------+-------+
| id | name |
+------+-------+
| 1 | hello |
+------+-------+
1 row in set (0.00 sec)

#id、name多个条件查询

mysql> select * from t1 where id=1 and name='hello';　　　　
+------+-------+
| id | name |
+------+-------+
| 1 | hello |
+------+-------+
1 row in set (0.00 sec)

#查看t1表结构

mysql> desc t1;　　　　　　　　　　　　　　　　　　
+-------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+-------+
| id | varchar(20) | YES | | NULL | |
| name | varchar(20) | YES | | NULL | |
+-------+-------------+------+-----+---------+-------+
2 rows in set (0.01 sec)

#刷新权限

mysql> flush privileges;　　　　　　　　　　　　　
Query OK, 0 rows affected (0.00 sec)

#清空表内容

mysql> delete from t1;　　　　　　　　　　　　　
Query OK, 1 row affected (0.09 sec)

mysql> desc t1;
+-------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+-------+
| id | varchar(20) | YES | | NULL | |
| name | varchar(20) | YES | | NULL | |
+-------+-------------+------+-----+---------+-------+
2 rows in set (0.00 sec)

mysql> select * from t1;
Empty set (0.00 sec)

#删除表

mysql> drop table t1;　　　　　　　　　　　　
Query OK, 0 rows affected (0.06 sec)

mysql> show tables;
Empty set (0.00 sec)

#删除mysql数据库

mysql> drop database mysql;　　　　　　　　

Query OK, 0 rows affected (0.00 sec)

#退出数据库

mysql> exit　　　　　　　　　　　　　　　　
Bye

#建立新的数据库用户，同时赋予该用户指定数据库内表的权限

mysql> grant insert,delete,update,select on 数据库.表名 to 数据库新用户@localhost identified by "符合强度的数据库用户密码";　
Query OK, 0 rows affected, 1 warning (0.00 sec)

 

#查询新用户feng的权限

mysql> show grants for feng@localhost;　　　　　　　　　
+------------------------------------------------------------------------------+
| Grants for feng@localhost |
+------------------------------------------------------------------------------+
| GRANT USAGE ON *.* TO 'feng'@'localhost' |
| GRANT SELECT, INSERT, UPDATE, DELETE ON `mysql`.`feng` TO 'feng'@'localhost' |
+------------------------------------------------------------------------------+
2 rows in set (0.00 sec)

 #查询当前所在的数据库位置

mysql> select database();　　　　　　　　　　　　　　
+------------+
| database() |
+------------+
| mysql |
+------------+
1 row in set (0.00 sec)

 #查询表名为feng的表的表结构信息

mysql> desc feng;　　　　　　　　　　　　　　　　　　　　　　　　
+-------+----------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+----------+------+-----+---------+-------+
| name | char(20) | YES | | NULL | |
| age | int(11) | YES | | NULL | |
| price | int(11) | YES | | NULL | |
+-------+----------+------+-----+---------+-------+
3 rows in set (0.00 sec)

#向表名为feng的表插入一行数据 

mysql> insert into feng(name,age,price) values('xiayu','20','999' );　　　　
Query OK, 1 row affected (0.01 sec)

mysql> insert into feng(name,age,price) values('shaoxian','10','299' );
Query OK, 1 row affected (0.12 sec)

mysql> insert into feng(name,age,price) values('ssin','20','39' );
Query OK, 1 row affected (0.01 sec)

#查询表名为feng的表中条件为“age<20”的全部符合条件的信息，其中通配符*表明全部

mysql> select * from feng where age<20;　　　　　　　　　　　　　
+----------+------+-------+
| name | age | price |
+----------+------+-------+
| shaoxian | 10 | 299 |
+----------+------+-------+
1 row in set (0.00 sec)

 #只查看表feng的name字段全部信息

mysql> select name from feng;　　　　　　　　　　　　　　　　　　
+----------+
| name |
+----------+
| xiayu |
| shaoxian |
| ssin |
+----------+
3 rows in set (0.00 sec)

 #更新表单feng中对应选项的值，其中199为新值，39为原始值

mysql> update feng set price=199 where price=39;　　　　　　　　
Query OK, 1 row affected (0.04 sec)
Rows matched: 1 Changed: 1 Warnings: 0

mysql> select * from feng;
+----------+------+-------+
| name | age | price |
+----------+------+-------+
| xiayu | 20 | 999 |
| shaoxian | 10 | 299 |
| ssin | 20 | 199 |
+----------+------+-------+
3 rows in set (0.00 sec)

 #delete删除表feng中符合条件的内容

mysql> delete from feng where price=199;　　　　　　　
Query OK, 1 row affected (0.04 sec)

mysql> select * from feng;
+----------+------+-------+
| name | age | price |
+----------+------+-------+
| xiayu | 20 | 999 |
| shaoxian | 10 | 299 |
+----------+------+-------+
2 rows in set (0.00 sec)

#delete删除表feng中的全部内容

mysql> delete from feng;　　　　　　　　　　　　　
Query OK, 2 rows affected (0.11 sec)

mysql> select * from feng;
Empty set (0.00 sec)

mysql> desc feng;
+-------+----------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+----------+------+-----+---------+-------+
| name | char(20) | YES | | NULL | |
| age | int(11) | YES | | NULL | |
| price | int(11) | YES | | NULL | |
+-------+----------+------+-----+---------+-------+
3 rows in set (0.00 sec)

 #备份lisi数据库为lisi.sql

[root@b ~]#mysqldump -uroot -pxxxxxxxx  lisi> lisi.sql　

#恢复mysql数据库　　　　　　　

[root@feng mnt]# mysql -u root -p mysql < mysqldb.dump　　　

 

向表中插入数据的2种方式：

mysql> insert into feng values('niu','2','9999');
Query OK, 1 row affected (0.00 sec)

mysql> insert into feng(price,name,age) values('8888','alice','16');
Query OK, 1 row affected (0.01 sec)

mysql> select * from feng;+-------+------+-------+| name | age | price |+-------+------+-------+| niu | 2 | 9999 || alice | 16 | 8888 |+-------+------+-------+2 rows in set (0.00 sec)