My mysql version is 5.7, according to the online tutorial to set the default character (utf8mb4), but only 2 items into effect, the result of the online is in addition to the filesystem will take effect,
about two days, because they do not set the character set, I insert data in the characters of the whole into a question mark,

In my web project, request access to the parameters are not gibberish, but it becomes a question mark when database is inserted in the