"Incorrect string value" when trying to insert UTF-8 into MySQL via JDBC?
jdbc, mysql, utf-8, utf8mb4
Solution
MySQL's `utf8` permits only the Unicode characters that can be represented with 3 bytes in UTF-8. Here you have a character that needs 4 bytes: \xF0\x90\x8D\x83 (U+10343 GOTHIC LETTER SAUIL).
If you have MySQL 5.5 or later you can change the column encoding from `utf8` to `utf8mb4`. This encoding allows storage of characters that occupy 4 bytes in UTF-8.
You may also have to set the server property `character_set_server` to `utf8mb4` in the MySQL configuration file. It seems that Connector/J defaults to 3-byte Unicode otherwise:
For example, to use 4-byte UTF-8 character sets with Connector/J, configure the MySQL server with `character_set_server=utf8mb4`, and leave `characterEncoding` out of the Connector/J connection string. Connector/J will then autodetect the UTF-8 setting.
Problem
This is how my connection is set: `Connection conn = DriverManager.getConnection(url + dbName + "?useUnicode=true&characterEncoding=utf-8", userName, password);` And I'm getting the following error when tyring to add a row to a table: `Incorrect string value: '\xF0\x90\x8D\x83\xF0\x90...' for column 'content' at row 1` I'm inserting thousands of records, and I always get this error when the text contains \xF0 (i.e. the the incorrect string value always starts with \xF0). The column's collation is utf8_general_ci. What could be the problem?