Exploring the Differences: utf8mb4 vs. utf8 Charsets in MySQL
MySQL offers a range of character sets, including utf8mb4 and utf8. While both are based on the UTF-8 encoding, they differ in their capabilities.
UTF-8 Encodings: A Review
ASCII: A 7-bit encoding supporting the English alphabet and common symbols.
UTF-8: A variable-length encoding that uses 1-4 bytes per code point.
UTF-16: A 16-bit encoding, primarily used in operating systems.
UTF-32: A 32-bit encoding, rarely utilized due to its high memory requirements.
utf8mb3 and utf8mb4
MySQL's "utf8" encoding, also known as "utf8mb3," stores a maximum of three bytes per code point. This encoding supports the "Basic Multilingual Plane" (BMP), which covers the range from 0x000 to 0xFFFF.
The "utf8mb4" encoding expands upon this by supporting four bytes per code point. This extended capability enables the storage of "supplemental characters" that fall outside the BMP, including emoji and certain Asian characters.
Benefits of utf8mb4 over utf8
- Wider Character Support: utf8mb4 can store characters from the entire Unicode character set, including those not supported by utf8mb3.
- No Data Loss: utf8mb3 columns cannot store supplemental characters. Upgrading from older versions of MySQL with utf8mb3 data to utf8mb4 does not result in data loss.
- Future-Proofing: As technology evolves and new Unicode characters are introduced, utf8mb4 ensures that your database can accommodate them.
In summary, if you require character support beyond the BMP or plan to future-proof your database, "utf8mb4" is the optimal choice.
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