MySQL error code

MySQL error 3755

MySQL server error 3755 is ER_CANNOT_DROP_COLUMN_FUNCTIONAL_INDEX, reported with SQLSTATE HY000.

Cannot drop column '%s' because it is used by a functional index. In order to drop the column, you must remove the functional index.

Error	3755
Name	ER_CANNOT_DROP_COLUMN_FUNCTIONAL_INDEX
SQLSTATE	HY000
Group	Server errors