In 5.7 (in contrast to 5.5 and 5.6), because of the different default value of the "sql_mode" variable, which now includes "STRICT_TRANS_TABLES", "ER_TRUNCATED_WRONG_VALUE_FOR_FIELD" (1366 Incorrect aaa value: 'bbb' for column 'ccc' at row ddd) is no longer considered a warning but is raised to an error.
In 5.7 (in contrast to 5.5 and 5.6), because of the different default value of the "sql_mode" variable, which now includes "STRICT_ TRANS_TABLES" , "ER_TRUNCATED_ WRONG_VALUE_ FOR_FIELD" (1366 Incorrect aaa value: 'bbb' for column 'ccc' at row ddd) is no longer considered a warning but is raised to an error.