


Detailed introduction to common Mysql instructions and Chinese garbled problems under Ubuntu
This article mainly introduces the common commands of Mysql under Ubuntu and the solutions to the Chinese garbled problem. Friends who need it can refer to it.
The following will introduce it to you. Mysql common commands and solving problems with Chinese garbled characters
Mysql system management commands
Log in to local Mysql
mysql -u username -p # 回车输入密码
or
mysql -u username -p passswd;
Log in to remote Mysql
mysql -h address -u username -p # 回车输入密码
or
mysql -h address -u username -p passswd;
Change new password
mysql> use mysql; mysql> update user set password=PASSWORD(‘newpasswd') where user='username'; mysql> flush privileges; #更新权限 mysql> quit; #退出
Add new user
mysql> grant select on database_name.* to user@address identified by ‘passwd'
ex: Add a user test1 with the password abc, allowing him to log in on any host and have query, insert, modify, and delete permissions on all databases.
mysql> grant select,insert,update,delete on . to root@localhost identified by 'mysql'; or mysql> grant all privileges on . to root@localhost identified by 'mysql'; mysql> flush privileges;
ex: If you do not want root to have a password to operate the data table in the database "mydb", you can issue another command to eliminate the password
mysql> grant select,insert,update,delete on mydb.* to root@localhost identified by '';
Delete user
mysql> delete from user where user='user_name' and host='address'; mysql> flush privileges; mysql> drop database dbname; #删除用户的数据库
Database import and export (mysqldump)
Export all databases
mysqldump -u user -p -A > backup_file_path
Export data and data structure
mysqldump -u user -p database_name_need_to_backup > backup_file_path ex00: export database mydb mysqldump -h localhost -u root -p mydb > ./mydb.sql ex01: export database mydb mytable mysqldump -h localhost -u root -p mydb mytable > ./mytable.sql ex02: export database mydb framework mysqldump -h localhost -u root -p mydb –add-drop-table > ./mydb_stru.sql
Only export data but not export Data structure
mysqldump -u user -p -t database_name_need_to_backup > backup_file_path
Export Events in the database
mysqldump -u user -p -E database_name_need_to_backup > backup_file_path
Export the stored procedures and functions in the database
mysqldump -u user -p -R database_name_need_to_backup > backup_file_path
from the outside FileImport databaseIn
Use the "source" command
mysql > source path_of_backup_file
Use the "
mysql -u root –p < path_of_backup_file
Mysql common instructions
View all databases
mysql> show databases;
Select the database to operate
mysql> use database_name;
View all tables under the current database
mysql> show tables;
Get the table structure
mysql> desc table_name;
or
mysql> show columns from table_name;
Create a database
mysql> create database database_name;
Delete a database
mysql> drop database database_name;
Create a table
mysql> create table table_name( uid bigint(20) not null, uname varchar(20) not null);
Delete a table
mysql> drop table table_name;
SQL insert statement
mysql> insert into table_name(col1, col2) values(value1, value2);
SQL update statement
mysql> update tablename set col1='value1', col2='value2' where wheredefinition;
SQL query statement
mysql> select * from table_name where....... #(最复杂的语句)
SQL delete statement
mysql> delete from table_name where...
Add fields to the table structure
mysql> alert table table_name add column field1 date, add column field2 time ...
Delete the fields of the table structure
mysql> alert table table_name drop field1;
View the structure of the table
mysql> show columns from table_name;
Use of limit
mysql> select * from table_name limit 3; #每页只显示3行 mysql> select * from table_name limit 3,4; #从查询结果的第三个开始,显示四项结果。 此处可很好的用来作分页处理。
Sort the query results
mysql> select * from table_name order by field1, orderby field2; #多重排序
View character encoding
mysql> show variables like 'character%' ;
Ubuntu mysql Chinese garbled solution
Openconfig file
sudo vim /etc/mysql/my.cnf
Find [mysqld] and add
character-set-server = utf8
Restart mysql
/etc/init.d/mysql restart 或者 service mysql restart
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