Connecting to MySQL Database Using the Command Line Client
Jul 07, 2025 am 01:50 AM
The most direct way to connect to a MySQL database is to use a command line client. First enter mysql -u username -p and correctly enter the password to enter the interactive interface; if you are connected to a remote database, you need to add the -h parameter to specify the host address. Secondly, you can directly switch to a specific database or execute SQL files when logging in, such as mysql -u username-p database name or mysql -u username-p database name
One of the most direct ways to connect to a MySQL database is to use a command line client. It is lightweight and flexible, suitable for developers and system administrators to operate databases quickly. Below are some practical operation methods and precautions.
Basic connection command
To connect to a MySQL server, the most basic command is:
mysql -u username -p
After entering this command, the system will prompt you to enter your password. After correct input, you can enter the interactive command line interface of MySQL.
If you are not connecting to the local database, but a remote server, you also need to add the host address:
mysql -u Username -p -h Host Address
For example:
mysql -u root -p -h 192.168.1.100
Make sure your users have remote access, otherwise you will encounter the problem of connection denied.
Specify the database using command line parameters
Sometimes you may want to log in to a specific database while logging in, you can do this:
mysql -u Username -p Database name
This way, you will switch to the database once you log in, eliminating the step of manually entering USE 數據庫名;
- If you also want to execute an SQL file, you can do this:
mysql -u Username-p Database name< File.sql
- Want to run the query immediately after connection? You can use the
-eparameter:mysql -u Username -p -e "SELECT * FROM table name" database name
This method is great for writing scripts or doing automated tasks.
Frequently Asked Questions and Solutions
Can't connect to the database?
- Make sure the MySQL service is running (can be viewed with
systemctl status mysql) - Check whether the username and password are correct
- If it is a remote connection, confirm whether the firewall has released port 3306.
- Check whether the target user has remote access permissions (set through
GRANT)
Connection is successful but the database cannot be operated?
It may be that there is insufficient permissions. You can log in with an account with administrator privileges to view the permission settings of the current user:
SHOW GRANTS FOR 'Username'@'Hostname';
If you find that some permissions are missing, you can use the following statement to authorize (taking SELECT permissions as an example):
GRANT SELECT ON Database name.Table name TO 'User name'@'Host name'; FLUSH PRIVILEGES;
Tips: Avoid plain text password exposure
Sometimes, in order to facilitate writing scripts, the password may be written directly in the command, such as:
mysql -u root -p password
Although this is feasible, it poses a security risk. A more recommended approach is to use configuration files to save credentials.
Create a .my.cnf file in your home directory, with the following content:
[client] user = root password = your password
Then set permissions to prevent leakage:
chmod 600 ~/.my.cnf
In this way, just run the mysql command and you can log in automatically, without manually entering your account password.
Basically that's it. Master these basic points, you should not encounter too many obstacles when connecting to MySQL using the command line every day.
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