Change the encoding of mysql
MySQL is a commonly used relational database management system that supports multiple character encodings. In actual use, you may encounter situations where certain characters cannot be displayed normally. In this case, you need to change the encoding settings of MySQL to solve this problem. This article will explain how to change the encoding of MySQL.
1. Understand MySQL encoding
MySQL encoding refers to the way data is stored, including character sets and sorting rules. MySQL supports multiple character sets, the more commonly used ones are UTF-8, GBK, Latin1, etc. Sorting rules specify comparison rules between characters, such as case sensitivity or insensitivity, character weights, etc.
2. Check the current encoding settings
Before changing the encoding, you first need to know the current encoding settings. You can view it with the following command:
show variables like '%char%';
This command will display the current MySQL character set and collation settings. The more commonly used variables include character_set_client, character_set_connection, character_set_database, character_set_results, character_set_server, etc.
3. Change the encoding settings
- Modify the configuration file
Changing the encoding settings of MySQL can be achieved by modifying the configuration file. Find the MySQL configuration file my.cnf (sometimes called my.ini) and add the following content:
[client] default-character-set=utf8 [mysql] default-character-set=utf8 [mysqld] collation-server = utf8_unicode_ci init-connect='SET NAMES utf8' character-set-server = utf8
Among them, default-character-set specifies that the default character set of the client and MySQL is UTF-8, collation-server specifies the collation rule as utf8_unicode_ci, and character-set-server specifies the server-side character set as UTF-8. init-connect specifies the SQL statement to be executed when the connection is established, which is used to set the character set to UTF-8.
- Modify an existing database
If you need to change the character set of an existing database to UTF-8, you can follow the steps below:
(1) Back up the original database
Use the mysqldump command to back up the original database to a file:
mysqldump -u root -p database > database.sql
(2) Change the database character set
Use the following command to backup the database The character set of the table in is changed to UTF-8:
ALTER TABLE tablename CONVERT TO CHARACTER SET utf8;
where tablename is the name of the table whose character set needs to be changed.
(3) Restore the backup file
Use the following command to restore the backup file to the database:
mysql -u root -p database < database.sql
4. Summary
MySQL encoding settings are for It is very important to ensure that the data is displayed and processed correctly. This article describes how to view the encoding settings of MySQL and how to implement the settings by modifying the configuration file and making changes to the existing database. In practice, the appropriate character set and collation should be selected as needed and appropriately tested and verified.
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