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MySQL error code

MySQL error 3907

MySQL server error 3907 is ER_FUNCTIONAL_INDEX_DATA_IS_TOO_LONG, reported with SQLSTATE 22001.

Data too long for functional index '%s'.
Error3907
NameER_FUNCTIONAL_INDEX_DATA_IS_TOO_LONG
SQLSTATE22001
GroupServer errors

In other databases

Source: MySQL 8.4 Error Reference