mysql utf8 garbled characters
May 20, 2023 am 11:44 AMWith the rapid development of Internet-related technologies, more and more people have begun to pay attention to the encoding of databases. Among them, the garbled problem of MySQL UTF8 encoding has particularly attracted people's attention. Although UTF-8, as one of the most popular character sets in the world, provides us with a more detailed and richer information encoding method, its garbled code problem is one of the problems that users hate.
In this article, I will take the garbled problem of MySQL UTF8 encoding as the starting point, discuss this problem in depth, and propose possible solutions.
1. Introduction to MySQL UTF8 encoding
UTF8 is an implementation of the UNICODE encoding standard. It is a variable-length encoding method that can be used to compress, store and transmit data. The biggest advantage of UTF8 encoding is that it has strong compatibility and can cover the encoding needs of almost all languages ??and texts.
MySQL UTF8 encoding refers to setting the character set to utf8 in MySQL (actually the encoding uses utf8mb4 by default, because utf8 does not support 4-byte characters). This setting can be applied to multiple languages, because UTF8-encoded data can be displayed on various platforms and is easy to operate in various programming languages. And with the rapid development of the current stage, UTF8 encoding will definitely become more and more important.
2. The reason why MySQL UTF8 encoding is garbled
Garbled characters refer to the phenomenon that some characters cannot be displayed normally when we operate the MySQL database. Due to the complexity of the UTF8 encoding scheme, the problem of MySQL UTF8 encoding garbled characters is also more complicated. The common reasons are as follows:
1. The characters stored in the database are in other encoding formats, or are mistaken for other encodings. The characters in the format are then displayed in UTF-8 encoding.
2. The data stored in the database in the program is actually an incomplete character because the encoding method used for this character is not UTF-8.
3. The encoding format is not specified during data query, resulting in a mismatch in encoding methods and garbled characters.
4. When using JDBC and other program libraries to connect, due to different connection methods and parameters, garbled characters may also occur.
5. When inputting to the MySQL database, characters that do not comply with the UTF-8 encoding format standard are used.
3. Solution to the MySQL UTF8 encoding garbled code
The solution to the MySQL UTF8 encoding garbled problem needs to be determined according to the actual situation. The following mainly introduces some common solutions:
1. Modify the MySQL encoding method
In order to solve the MySQL UTF8 encoding garbled problem, the best way is to modify the encoding method to utf8mb4. utf8mb4 is a superset of UTF8, supporting a complete encoding of four bytes. Its method is more unified and standardized than utf8, and can avoid garbled characters. Modifications in MySQL are not complicated. You only need to add the following code to the my.cnf file of MySQL:
character_set_server=utf8mb4
collation-server=utf8mb4_general_ci
2. Modify the encoding method in the program
If the database encoding is correct, then the cause of garbled characters is likely to be the inconsistent encoding method in the program. In this case, the problem can be solved by modifying the coding in the program. Commonly used encoding methods include UTF-8, GB2312, GBK, BIG5, etc. You can make corresponding modifications according to the encoding method used.
3. Specify the encoding method
Add "SET NAMES utf8mb4" and other statements in the SQL statement to specify the encoding method, which is equivalent to converting the output result to the specified encoding to avoid garbled characters.
4. Configure the encoding when using Java to connect to the MySQL database
When using Java to connect to the MySQL database, you need to specify the character set encoding in the URL, such as jdbc:mysql://localhost:3306/ database_name?useUnicode=true&characterEncoding=UTF-8&autoReconnect=true&zeroDateTimeBehavior=convertToNull, where the characterEncoding=UTF-8 parameter is used to specify the encoding method.
5. Character set conversion
If the encoding method cannot be modified for some reasons, or the character set in the data source is another encoding method, then character set conversion is required. In actual operation, you can use some tools such as iconv and other programs to perform conversion to achieve the desired effect.
4. Summary
Don’t worry too much if you encounter the MySQL UTF8 encoding garbled problem in actual work, because since this problem exists, there must be a certain solution. In general, there are roughly the above five methods to solve the problem of MySQL UTF8 encoding garbled characters. However, according to different specific situations, we need to take appropriate measures to deal with the garbled code problem. This requires us to carefully analyze the specific causes of the problem in actual operations and handle it with corresponding solutions. In the end, as long as appropriate measures are taken, the desired results can often be achieved and unnecessary troubles and disputes can be avoided.
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