Special characters records storage problems

solution:

Database settings: utf8mb4 (which is most of the online solutions)

But if the set is not successful, check the version of the database connection

<dependency> 
    <groupId> MySQL </ groupId> 
    <artifactId> MySQL-Connector-the Java </ artifactId> 
    <Version> 8.0.16 </ Version> 
    <scope> Runtime </ scope> 
</ dependency> 
Local database version before the author 8.0, did not find problems, but the online database version 5.7, 
you need to modify the database connection version can be resolved