Mysql learning-Basic use

Mysql learning-once the installation is complete, the MySQL server should be started automatically. Sudostartmysql # Start sudostopmysql manually # Stop it manually. After you modify the configuration file, restart mysqld to make the changes take effect. To check whether the mysqld process is enabled, run the following command: pg

Mysql learning-once the installation is complete, the MySQL server should be started automatically. Sudo start mysql # start sudo stop mysql manually # stop it manually. After you modify the configuration file, restart mysqld to make the changes take effect. To check whether the mysqld process is enabled, run the following command: pg

Mysql learning-basic usage

Once the installation is complete, the MySQL server should be started automatically.

Sudo start mysql # start it manually

Sudo stop mysql # manually stop

After you modify the configuration file, you need to restart mysqld to make these changes take effect.

To check whether the mysqld process is enabled, run the following command:

pgrep mysqld

If the process is enabled, the command returns the id of the process.

MySQL configuration file:/etc/mysql/my. cnf, which specifies the data file storage path

datadir         = /var/lib/mysql

If you create a database named test, the data in the database will be stored in the/var/lib/mysql/test directory.

Go to MySQL

mysql -u root -p 

(Enter the mysql root Password)

qii@ubuntu:~$ mysql -u root -pEnter password: Welcome to the MySQL monitor.  Commands end with ; or \g.Your MySQL connection id is 37Server version: 5.1.41-3ubuntu12.3 (Ubuntu)Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.mysql> 

Modify the MySQL administrator password:

sudo mysqladmin -u root password newpassword；

View the databases owned by the current user:

Mysql> show databases
->;
+ -------------------- +
| Database |
+ -------------------- +
| Information_schema |
| Mysql |
| Performance_schema |
+ -------------------- +
3 rows in set (0.19 sec)

View the databases available to the current user:

Mysql> show databases
->;
+ -------------------- +
| Database |
+ -------------------- +
| Information_schema |
| Mysql |
| Performance_schema |
+ -------------------- +
3 rows in set (0.19 sec)

Mysql> show tables
->;
ERROR 1046 (3D000): No database selected
Mysql> select table_name from user_tables;
ERROR 1046 (3D000): No database selected
Mysql> show databases;
+ -------------------- +
| Database |
+ -------------------- +
| Information_schema |
| Mysql |
| Performance_schema |
+ -------------------- +
3 rows in set (0.00 sec)

Select the current database:

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-

Database changed

View tables in the current database:
Mysql> show tables
->;
+ --------------------------- +
| Tables_in_mysql |
+ --------------------------- +
| Columns_priv |
| Db |
| Event |
| Func |
| General_log |
| Help_category |
| Help_keyword |
| Help_relation |
| Help_topic |
| Host |
| Ndb_binlog_index |
| Plugin |
| Proc |
| Procs_priv |
| Proxies_priv |
| Servers |
| Slow_log |
| Tables_priv |
| Time_zone |
| Time_zone_leap_second |
| Time_zone_name |
| Time_zone_transition |
| Time_zone_transition_type |
| User |
+ --------------------------- +
24 rows in set (0.00 sec)

View the details of a table:

Mysql> describe servers;
+ ------------- + ---------- + ------ + ----- + --------- + ------- +
| Field | Type | Null | Key | Default | Extra |
+ ------------- + ---------- + ------ + ----- + --------- + ------- +
| Server_name | char (64) | NO | PRI |
| Host | char (64) | NO |
| Db | char (64) | NO |
| Username | char (64) | NO |
| Password | char (64) | NO |
| Port | int (4) | NO | 0 |
| Socket | char (64) | NO |
| Wrapper | char (64) | NO |
| Owner | char (64) | NO |
+ ------------- + ---------- + ------ + ----- + --------- + ------- +
9 rows in set (0.04 sec)