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MySQL Unicode Warning

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It’s always interesting when I upgrade from one release to the next. I learn new things, and in the case of MySQL’s installation and maintenance I become more grateful for the great team of developers working to produce MySQL 8.

A warning that caught my eye in MySQL 8 (8.0.21) was this one on Unicode with the utf8 character code:

Warning (code 3719): 'utf8' is currently an alias for the character set UTF8MB3, but will be an alias for UTF8MB4 in a future release. Please consider using UTF8MB4 in order to be unambiguous.

Currently, a character alias for utf8mb3 is an alias for the deprecated utf8mb3 (a 3-byte character set) until it is removed. When the utf8mb3 character set is removed in a subsequent release the utf8 alias will represent the utf8mb4 (a 4-byte character set), which includes BMP and supplemental character support.

It appears to me that its probably a good time to proactively provision disk space for an upgrade to utf8mb4 (a 4-byte character set). It also probably time to use the utf8mb4 character set rather than the utf8 character set alias. The MySQL Server team wrote a blog entry on the when to use which one. Naturally, all this will have a substantial impact on disk space allocated to the database.

Written by maclochlainn

September 29th, 2020 at 8:24 am