utf8mb4
UTF8MB4, commonly written as utf8mb4, is a MySQL character set that encodes Unicode text using up to four bytes per character. It implements the full UTF-8 encoding, capable of representing all Unicode code points from U+0000 to U+10FFFF. This includes emoji and other characters outside the older three-byte range.
Historically, MySQL offered a utf8 character set that was limited to three bytes per character and could
Technical notes: utf8mb4 uses 1 to 4 bytes per character and is compatible with standard UTF-8 semantics.
Usage considerations: For new databases, utf8mb4 should be the default character set. When migrating from utf8,