分表后mybatis-plus删除操作失效等问题处理

因为重构dao层，问题太多了，于是想着另起一个章节。
4 count的问题
使用count复用，不需要查询所有字段，否则会出现下面的错误

### SQL: SELECT COUNT(  t.id,t.company_id,t.user_id,t.bind_time,t.role_type,t.job_type,t.student_class,t.is_current,t.used_time,t.is_operational,t1.name AS name,t1.type AS name,t1.tax_no AS name,t1.tel AS name,t1.province AS name,t1.city AS name,t1.area AS name,t1.address AS name,t1.status AS name,t1.creator_id AS name  ) FROM eayc_company_user  t    INNER JOIN eayc_company t1 ON (t1.id = t.company_id)      WHERE   (t1.status = ? AND t.user_id = ?)
### Cause: java.sql.SQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 't.company_id,t.user_id,t.bind_time,t.role_type,t.job_type,t.student_class,t.is_c' at line 2
; bad SQL grammar []; nested exception is java.sql.SQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 't.company_id,t.user_id,t.bind_time,t.role_type,t.job_type,t.student_class,t.is_c' at line 2at org.springframework.jdbc.support.SQLErrorCodeSQLExceptionTranslator.doTranslate(SQLErrorCodeSQLExceptionTranslator.java:239)at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:70)at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:91)at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:441)at com.sun.proxy.$Proxy161.selectOne(Unknown Source)at org.mybatis.spring.SqlSessionTemplate.selectOne(SqlSessionTemplate.java:160)at com.baomidou.mybatisplus.core.override.MybatisMapperMethod.execute(MybatisMapperMethod.java:89)at com.baomidou.mybatisplus.core.override.MybatisMapperProxy$PlainMethodInvoker.invoke(MybatisMapperProxy.java:148)at com.baomidou.mybatisplus.core.override.MybatisMapperProxy.invoke(MybatisMapperProxy.java:89)at com.sun.proxy.$Proxy174.selectJoinCount(Unknown Source)at com.github.yulichang.base.MPJBaseService.selectJoinCount(MPJBaseService.java:54)at com.whty.eayc.user.service.base.impl.EaycCompanyUserServiceImpl.count(EaycCompanyUserServiceImpl.java:156)

处理方案,如下即可

 MPJLambdaWrapper<EaycCompanyUser> mpjLambdaWrapper = new MPJLambdaWrapper<>();mpjLambdaWrapper.select("1").innerJoin(EaycCompany.class,EaycCompany::getId,EaycCompanyUser::getCompanyId);

3 mybatis封装对象的问题
直接使用mybatis自身的对象，会有问题，他的列表对象会设置一个id，导致后续的工程会出问题

 <select id="getStatementDefaultEquations" resultMap="defaultEquationsMap">select<include refid="com.whty.acc.setting.dao.AccStatementMapper.Base_Column_List_Udf"></include>,<include refid="com.whty.acc.setting.dao.AccStatementDefaultMapper.Base_Column_List_Udf"></include>from acc_statement accStatementleft join acc_statement_default accStatementDefaulton accStatement.id = accStatementDefault.sheet_idwhere accStatement.accounting_standard = #{standard}and accStatement.type = #{type}order by accStatement.id, accStatementDefault.id</select><resultMap id="defaultEquationsMap" type="com.whty.acc.setting.dto.dto.StatementDefaultEquationDto" extends="com.whty.acc.setting.dao.AccStatementMapper.BaseResultMapUdf"><collection property="accStatementDefaults" ofType="com.whty.acc.setting.pojo.AccStatementDefault" resultMap="com.whty.acc.setting.dao.AccStatementDefaultMapper.BaseResultMapUdf"></collection></resultMap>

调整如下,按照mybatis的写法，对象才能封装正确

@Overridepublic List<StatementDefaultEquationDto> getStatementDefaultEquations(String type, String standard) {MPJLambdaWrapper<AccStatement> mpjLambdaWrapper = new MPJLambdaWrapper<>();mpjLambdaWrapper.selectAll(AccStatement.class).selectCollection(AccStatementDefault.class,StatementDefaultEquationDto::getAccStatementDefaults).leftJoin(AccStatementDefault.class,AccStatementDefault::getSheetId,AccStatement::getId);mpjLambdaWrapper.eq(AccStatement::getAccountingStandard,standard);mpjLambdaWrapper.eq(AccStatement::getType,type);mpjLambdaWrapper.orderByAsc(AccStatement::getId);mpjLambdaWrapper.orderByAsc(AccStatementDefault::getId);return selectJoinList(StatementDefaultEquationDto.class,mpjLambdaWrapper);}

2 看似是空指针异常，实则与mybatis-plus写法有关系。

09:54:55.293 ERROR c.w.a.s.controller.AccBalanceSheetController - null
java.lang.NullPointerException: nullat com.whty.acc.statement.service.ext.impl.AccBalanceSheetExtServiceImpl.genBalanceAndNoteBySimpleDto(AccBalanceSheetExtServiceImpl.java:1333)at com.whty.acc.statement.service.ext.impl.AccBalanceSheetExtServiceImpl.genSheetLineBalanceBySimpleDto(AccBalanceSheetExtServiceImpl.java:1257)at com.whty.acc.statement.service.ext.impl.AccBalanceSheetExtServiceImpl.assetsBySimpleDto(AccBalanceSheetExtServiceImpl.java:574)at com.whty.acc.statement.service.ext.impl.AccBalanceSheetExtServiceImpl.getDataBySimpleDto(AccBalanceSheetExtServiceImpl.java:392)at com.whty.acc.statement.service.ext.impl.AccBalanceSheetExtServiceImpl.getBalanceSheet(AccBalanceSheetExtServiceImpl.java:158)at com.whty.acc.statement.service.ext.impl.AccBalanceSheetExtServiceImpl$$FastClassBySpringCGLIB$$4edc7667.invoke(<generated>)

java.lang.NullPointerException: nullat com.whty.acc.statement.service.ext.impl.AccCashFlowEquationServiceImpl.lambda$getEquationDtos$3(AccCashFlowEquationServiceImpl.java:170)at java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:174)at java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1382)at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481)at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471)at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:708)at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)at java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:499)at com.whty.acc.statement.service.ext.impl.AccCashFlowEquationServiceImpl.getEquationDtos(AccCashFlowEquationServiceImpl.java:170)at com.whty.acc.statement.service.ext.impl.AccCashFlowEquationServiceImpl.getCashFlowByEquation(AccCashFlowEquationServiceImpl.java:87)at com.whty.acc.statement.service.ext.impl.AccCashFlowSheetExtServiceImpl.getCashFlowSheetDtos(AccCashFlowSheetExtServiceImpl.java:91)at com.whty.acc.statement.service.ext.impl.AccCashFlowSheetExtServiceImpl$$FastClassBySpringCGLIB$$3b4f4002.invoke(<generated>)

1 分表后没有生产导致sql异常
下面这个语句咋一看是没有任何问题的，但实际根本没有acc_voucher这张表，因为数据库做了分表。
所以问题在为什么mybatis-plus后，delete操作分表没有生效。
下面是正常情况，ShardingSphere-SQL会做一次翻译
1
但下面删除操作却没有，为什么呢？

### SQL: DELETE FROM    acc_voucher t           WHERE   (t.as_id = ? AND t.id = ?)
### Cause: java.sql.SQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 't WHERE (t.as_id = 92293 AND t.id = 2)' at line 2
; bad SQL grammar []; nested exception is java.sql.SQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 't WHERE (t.as_id = 92293 AND t.id = 2)' at line 2at org.springframework.jdbc.support.SQLErrorCodeSQLExceptionTranslator.doTranslate(SQLErrorCodeSQLExceptionTranslator.java:239)at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:70)at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:91)at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:441)at com.sun.proxy.$Proxy169.delete(Unknown Source)at org.mybatis.spring.SqlSessionTemplate.delete(SqlSessionTemplate.java:304)at com.baomidou.mybatisplus.core.override.MybatisMapperMethod.execute(MybatisMapperMethod.java:69)at com.baomidou.mybatisplus.core.override.MybatisMapperProxy$PlainMethodInvoker.invoke(MybatisMapperProxy.java:148)at com.baomidou.mybatisplus.core.override.MybatisMapperProxy.invoke(MybatisMapperProxy.java:89)at com.sun.proxy.$Proxy174.delete(Unknown Source)at com.baomidou.mybatisplus.extension.service.IService.remove(IService.java:149)at com.whty.acc.voucher.service.base.impl.AccVoucherServiceImpl.deleteByPrimaryKey(AccVoucherServiceImpl.java:89)at com.whty.acc.voucher.service.base.impl.AccVoucherServiceImpl$$FastClassBySpringCGLIB$$f3310a26.invoke(<generated>)at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218)at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:793)at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163)at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763)at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:123)at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:388)at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:119)at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763)at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:708)at com.whty.acc.voucher.service.base.impl.AccVoucherServiceImpl$$EnhancerBySpringCGLIB$$9a0ca76a.deleteByPrimaryKey(<generated>)at com.whty.acc.voucher.service.dubbo.consume.impl.AccVoucherDubboConsumeImpl.remove(AccVoucherDubboConsumeImpl.java:101)at com.whty.acc.voucher.service.dubbo.consume.impl.AccVoucherDubboConsumeImpl.removeByLock(AccVoucherDubboConsumeImpl.java:79)at com.whty.acc.voucher.service.dubbo.consume.impl.AccVoucherDubboConsumeImpl$$FastClassBySpringCGLIB$$e041f606.invoke(<generated>)at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218)at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:793)at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163)at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763)at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:123)at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:388)at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:119)at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763)at org.springframework.aop.aspectj.AspectJAfterAdvice.invoke(AspectJAfterAdvice.java:49)at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:175)at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763)at org.springframework.aop.framework.adapter.MethodBeforeAdviceInterceptor.invoke(MethodBeforeAdviceInterceptor.java:58)at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:175)at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763)at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:97)at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763)at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:708)at com.whty.acc.voucher.service.dubbo.consume.impl.AccVoucherDubboConsumeImpl$$EnhancerBySpringCGLIB$$c79c2987.removeByLock(<generated>)at com.whty.acc.voucher.controller.AccVoucherController.remove(AccVoucherController.java:583)at com.whty.acc.voucher.controller.AccVoucherController$$FastClassBySpringCGLIB$$271f1de3.invoke(<generated>)at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218)at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:793)at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163)at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763)at org.springframework.validation.beanvalidation.MethodValidationInterceptor.invoke(MethodValidationInterceptor.java:123)at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763)at org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed(MethodInvocationProceedingJoinPoint.java:102)at com.whty.acc.setting.annotation.WebLogAspect.around(WebLogAspect.java:60)at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)at java.lang.reflect.Method.invoke(Method.java:498)at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:634)at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:624)at org.springframework.aop.aspectj.AspectJAroundAdvice.invoke(AspectJAroundAdvice.java:72)at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:175)at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763)at org.springframework.aop.framework.adapter.MethodBeforeAdviceInterceptor.invoke(MethodBeforeAdviceInterceptor.java:58)at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:175)at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763)at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:97)at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763)at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:708)at com.whty.acc.voucher.controller.AccVoucherController$$EnhancerBySpringCGLIB$$ca9bb02d.remove(<generated>)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 org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205)at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:150)at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:117)at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895)at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:808)at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1071)at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:964)at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)at org.springframework.web.servlet.FrameworkServlet.doDelete(FrameworkServlet.java:931)at javax.servlet.http.HttpServlet.service(HttpServlet.java:671)at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)at javax.servlet.http.HttpServlet.service(HttpServlet.java:750)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)at com.whty.framework.web.filter.CorsFilter.doFilter(CorsFilter.java:41)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100)at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93)at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:177)at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97)at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541)at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135)at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78)at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:360)at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:399)at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:891)at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1784)at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191)at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)at java.lang.Thread.run(Thread.java:748)

查看删除操作的代码

 @Transactional@Overridepublic boolean deleteByPrimaryKey(Integer asId, Integer id) {MPJLambdaWrapper<AccVoucher> mpjLambdaWrapper = new MPJLambdaWrapper<>();mpjLambdaWrapper.eq(AccVoucher::getAsId,asId);mpjLambdaWrapper.eq(AccVoucher::getId,id);return remove(mpjLambdaWrapper);}

调整如下,问题就解决了，看来问题在MPJLambdaWrapper，对分表的删除操作有影响。

 @Transactional@Overridepublic boolean deleteByPrimaryKey(Integer asId, Integer id) {LambdaQueryWrapper<AccVoucher> mpjLambdaWrapper = new LambdaQueryWrapper<>();mpjLambdaWrapper.eq(AccVoucher::getAsId,asId);mpjLambdaWrapper.eq(AccVoucher::getId,id);return remove(mpjLambdaWrapper);}

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