UTF-8 and UTF8MB4 in MySQL: Difference
In MySQL databases, character set selection is critical to the storage and processing of data.
Among them, UTF-8 and UTF8MB4 are two common character set options.
So, what is the difference between them?
1. Introduction to the character set
UTF-8
- UTF-8（8-bit Unicode Transformation Format）
- It is a variable-length character encoding method that can represent almost all characters in the world.
- It uses 1 to 4 bytes to represent a character, depending on the encoding range of the characters.
UTF8MB4
- UTF8MB4（UTF-8 Multibyte 4）
- is a superset of UTF-8, which extends the encoding range of UTF-8.
- It can represent more characters, including some rare characters and emoji expressions, etc.
2. Detailed explanation of the differences
1. Coding range
- UTF-8 can represent most common characters, but may not be expressed correctly for some rare characters and emoji expressions.
- UTF8MB4 can represent almost all Unicode characters, including those that UTF-8 cannot represent.
2. Storage requirements
- Since UTF8MB4 can represent more characters, it usually requires more storage than UTF-8.
- Specifically, UTF8MB4 may need to use 1 to 4 bytes to represent a character, while UTF-8 usually only needs to use 1 to 3 bytes.
3. Compatibility
- UTF-8 is a widely used character set that is supported by almost all operating systems and programming languages. Therefore, if you need to exchange data with other systems, UTF-8 may be a better option.
- Although UTF8MB4 can represent more characters, not all systems support it. When using UTF8MB4, you need to make sure that both your application and database server support this character set.
3. Choose suggestions
- If your application only needs to handle common characters, UTF-8 may be a good choice. It has wide compatibility and low storage requirements.
- If your application needs to deal with some rare characters or emoji emojis, etc., then UTF8MB4 may be a better choice. It ensures that your data can correctly store and display all characters.
- When selecting a character set, the performance and storage requirements of the database need to be considered. If your database stores a large amount of text data, choosing a suitable character set can improve the performance and storage efficiency of the database.
Anyway
UTF-8 and UTF8MB4 are both commonly used character set options in MySQL. The differences between them are mainly in encoding range, storage requirements, and compatibility.
When selecting a character set, you need to choose according to the specific needs of your application to ensure that your data can be stored and displayed correctly.
The above is personal experience. I hope you can give you a reference and I hope you can support me more.