問題一：

Failed to execute goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.5:generate (default-cli) on project miaosha: Unknown system variable 'query_cache_size'

解決一：

如果出現此問題，說明同行者你是在此課程出來后很久才開始學習！

所以只需要改變mysql的版本就可以了，我改成了8.0.27版本

<groupId>mysql</groupId>
??<artifactId>mysql-connector-java</artifactId>
??<version>8.0.27</version>
</dependency>

問題二：

?Failed to execute goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.5:generate (default-cli) on project miaosha: Execution default-cli of goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.5:generate failed: An API incompatibility was encountered while executing org.mybatis.generator:mybatis-generator-maven-plugin:1.3.5:generate: java.lang.NoSuchMethodError: org.mybatis.generator.internal.ObjectFactory.addResourceClassLoader(Ljava/lang/ClassLoader;)V

解決二：

將plugins中的下面的依賴，先拿到plugins外面一層，刷新maven，然后放回去，即可解決

<dependency>
??<groupId>org.mybatis.generator</groupId>
??<artifactId>mybatis-generator-core</artifactId>
??<version>1.3.5</version>
</dependency>