報了一個Mybatis的錯：
nested exception is org.apache.ibatis.exceptions.TooManyResultsException: Expected one result (or null) to be returned by selectOne(), but found: 4
即:期望selectOne()返回一個結果(或null)，但是卻有4條結果。
2019-06-20 09:48:10.618 ERROR 10911 --- [nio-8080-exec-7] o.s.boot.web.support.ErrorPageFilter : Forwarding to error page from request [/Household/saveHouseHold] due to exception [nested exception is org.apache.ibatis.exceptions.TooManyResultsException: Expected one result (or null) to be returned by selectOne(), but found: 4]
org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.TooManyResultsException: Expected one result (or null) to be returned by selectOne(), but found: 4
at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:77) ~[mybatis-spring-1.3.1.jar:1.3.1]
at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:446) ~[mybatis-spring-1.3.1.jar:1.3.1]
at com.sun.proxy.$Proxy84.selectOne(Unknown Source) ~[na:na]
at org.mybatis.spring.SqlSessionTemplate.selectOne(SqlSessionTemplate.java:166) ~[mybatis-spring-1.3.1.jar:1.3.1]
at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:82) ~[mybatis-3.4.5.jar:3.4.5]
at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:59) ~[mybatis-3.4.5.jar:3.4.5]
at com.sun.proxy.$Proxy104.getTcUserByOpenid(Unknown Source) ~[na:na]
at com.motors.jmtbt.service.impl.BtUserServiceImpl.getTcUserByOpenid(BtUserServiceImpl.java:38) ~[classes/:na]
at com.motors.jmtbt.controller.HouseholdController.saveHouseHold(HouseholdController.java:215) ~[classes/:na]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_191]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_191]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_191]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_191]
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205) ~[spring-web-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:133) ~[spring-web-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:97) ~[spring-webmvc-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827) ~[spring-webmvc-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738) ~[spring-webmvc-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) ~[spring-webmvc-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967) ~[spring-webmvc-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901) ~[spring-webmvc-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970) ~[spring-webmvc-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872) ~[spring-webmvc-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:661) ~[servlet-api.jar:na]
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) ~[spring-webmvc-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) ~[servlet-api.jar:na]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) [catalina.jar:8.5.31]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:8.5.31]
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) ~[tomcat-websocket.jar:8.5.31]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:8.5.31]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:8.5.31]
at com.motoros.web.filter.firewall.FireWallFilter.doFilter(FireWallFilter.java:30) ~[general-module-1.0-SNAPSHOT.jar:na]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:8.5.31]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:8.5.31]
at org.springframework.boot.web.filter.ApplicationContextHeaderFilter.doFilterInternal(ApplicationContextHeaderFilter.java:55) ~[spring-boot-1.5.10.RELEASE.jar:1.5.10.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:8.5.31]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:8.5.31]
at com.alibaba.druid.support.http.WebStatFilter.doFilter(WebStatFilter.java:123) ~[druid-1.1.7.jar:1.1.7]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:8.5.31]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:8.5.31]
at org.springframework.boot.actuate.trace.WebRequestTraceFilter.doFilterInternal(WebRequestTraceFilter.java:110) ~[spring-boot-actuator-1.5.10.RELEASE.jar:1.5.10.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:8.5.31]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:8.5.31]
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) ~[spring-web-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:8.5.31]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:8.5.31]
at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:108) ~[spring-web-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:8.5.31]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:8.5.31]
at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:81) ~[spring-web-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:8.5.31]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:8.5.31]
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197) ~[spring-web-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:8.5.31]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:8.5.31]
at org.springframework.boot.actuate.autoconfigure.MetricsFilter.doFilterInternal(MetricsFilter.java:106) ~[spring-boot-actuator-1.5.10.RELEASE.jar:1.5.10.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:8.5.31]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:8.5.31]
at org.springframework.boot.web.support.ErrorPageFilter.doFilter(ErrorPageFilter.java:115) [spring-boot-1.5.10.RELEASE.jar:1.5.10.RELEASE]
at org.springframework.boot.web.support.ErrorPageFilter.access$000(ErrorPageFilter.java:59) [spring-boot-1.5.10.RELEASE.jar:1.5.10.RELEASE]
at org.springframework.boot.web.support.ErrorPageFilter$1.doFilterInternal(ErrorPageFilter.java:90) [spring-boot-1.5.10.RELEASE.jar:1.5.10.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.boot.web.support.ErrorPageFilter.doFilter(ErrorPageFilter.java:108) [spring-boot-1.5.10.RELEASE.jar:1.5.10.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:8.5.31]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:8.5.31]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198) [catalina.jar:8.5.31]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [catalina.jar:8.5.31]
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:496) [catalina.jar:8.5.31]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [catalina.jar:8.5.31]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81) [catalina.jar:8.5.31]
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:650) [catalina.jar:8.5.31]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [catalina.jar:8.5.31]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) [catalina.jar:8.5.31]
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:803) [tomcat-coyote.jar:8.5.31]
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-coyote.jar:8.5.31]
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790) [tomcat-coyote.jar:8.5.31]
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1468) [tomcat-coyote.jar:8.5.31]
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-coyote.jar:8.5.31]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_191]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_191]
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-util.jar:8.5.31]
at java.lang.Thread.run(Thread.java:748) [na:1.8.0_191]
Caused by: org.apache.ibatis.exceptions.TooManyResultsException: Expected one result (or null) to be returned by selectOne(), but found: 4
at org.apache.ibatis.session.defaults.DefaultSqlSession.selectOne(DefaultSqlSession.java:81) ~[mybatis-3.4.5.jar:3.4.5]
at sun.reflect.GeneratedMethodAccessor130.invoke(Unknown Source) ~[na:na]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_191]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_191]
at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:433) ~[mybatis-spring-1.3.1.jar:1.3.1]
... 87 common frames omitted
原因很簡單，就是如錯誤說明那般，數據庫中本應該只有一條符合的結果，現在查的時候，卻發現有多條結果符合的結果，刪除多餘的就OK了。