删除分类是不是可以优化?

删除分类的时候，如果没有删除三级分类，直接删除二级分类是不是会报错？必须把三级分类删除完了，才能删除二级分类，可以优化成点击删除二级分类的时候就直接把下属的三级分类删除掉吗？

java.lang.reflect.InvocationTargetException

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

at java.lang.reflect.Method.invoke(Method.java:498)

at com.imooc.icake.global.GlobalController.service(GlobalController.java:60)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)

at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)

at com.imooc.icake.global.LoginFilter.doFilter(LoginFilter.java:20)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)

at com.imooc.icake.global.EncodingFilter.doFilter(EncodingFilter.java:31)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)

at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199)

at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)

at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:543)

at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)

at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)

at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:690)

at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)

at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)

at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:615)

at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)

at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:818)

at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1627)

at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)

at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)

at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)

at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)

at java.lang.Thread.run(Thread.java:748)

Caused by: org.apache.ibatis.exceptions.PersistenceException:

### Error updating database. Cause: java.sql.SQLIntegrityConstraintViolationException: Cannot delete or update a parent row: a foreign key constraint fails (`icake`.`catalog`, CONSTRAINT `FK_Reference_2` FOREIGN KEY (`pid`) REFERENCES `catalog` (`id`) ON DELETE RESTRICT ON UPDATE RESTRICT)

### The error may exist in com/imooc/icake/dao/CatalogDao.java (best guess)

### The error may involve com.imooc.icake.dao.CatalogDao.delete-Inline

### The error occurred while setting parameters

### SQL: delete from catalog where id=?

### Cause: java.sql.SQLIntegrityConstraintViolationException: Cannot delete or update a parent row: a foreign key constraint fails (`icake`.`catalog`, CONSTRAINT `FK_Reference_2` FOREIGN KEY (`pid`) REFERENCES `catalog` (`id`) ON DELETE RESTRICT ON UPDATE RESTRICT)

at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:30)

at org.apache.ibatis.session.defaults.DefaultSqlSession.update(DefaultSqlSession.java:199)

at org.apache.ibatis.session.defaults.DefaultSqlSession.delete(DefaultSqlSession.java:212)

at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:72)

at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:58)

at com.sun.proxy.$Proxy18.delete(Unknown Source)

at com.imooc.icake.biz.impl.CatalogBizImpl.remove(CatalogBizImpl.java:27)

at com.imooc.icake.controller.CatalogController.remove(CatalogController.java:66)

... 33 more

Caused by: java.sql.SQLIntegrityConstraintViolationException: Cannot delete or update a parent row: a foreign key constraint fails (`icake`.`catalog`, CONSTRAINT `FK_Reference_2` FOREIGN KEY (`pid`) REFERENCES `catalog` (`id`) ON DELETE RESTRICT ON UPDATE RESTRICT)

at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:117)

at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97)

at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:122)

at com.mysql.cj.jdbc.ClientPreparedStatement.executeInternal(ClientPreparedStatement.java:953)

at com.mysql.cj.jdbc.ClientPreparedStatement.execute(ClientPreparedStatement.java:370)

at org.apache.ibatis.executor.statement.PreparedStatementHandler.update(PreparedStatementHandler.java:47)

at org.apache.ibatis.executor.statement.RoutingStatementHandler.update(RoutingStatementHandler.java:74)

at org.apache.ibatis.executor.SimpleExecutor.doUpdate(SimpleExecutor.java:50)

at org.apache.ibatis.executor.BaseExecutor.update(BaseExecutor.java:117)

at org.apache.ibatis.executor.CachingExecutor.update(CachingExecutor.java:76)

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)