Couchbase & Spring 查询错误：“返回原始类型的查询预计将返回 1 个结果

Question

在我们的spring-boot 2.0.4.RELEASE应用程序中，我们使用Couchbase version 5.5.1 build 3511with Spring。我们在 Repository 接口中添加了一个新的删除方法：public interface CatRepository extends CouchbaseRepository<Cat, String> {  long deleteAllByName(String name);调用该方法时，文档从存储桶中删除，但我们收到以下错误：返回原始类型的查询预计将返回 1 个结果，得到 X该X 值根据删除的项目数而变化。在下面的示例中，删除了 27 个项目。这是完整的堆栈跟踪：    Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.data.couchbase.core.CouchbaseQueryExecutionException: Query returning a primitive type are expected to return exactly 1 result, got 27] with root causeorg.springframework.data.couchbase.core.CouchbaseQueryExecutionException: Query returning a primitive type are expected to return exactly 1 result, got 27    at org.springframework.data.couchbase.repository.query.AbstractN1qlBasedQuery.executeSingleProjection(AbstractN1qlBasedQuery.java:203) ~[spring-data-couchbase-3.0.9.RELEASE.jar:3.0.9.RELEASE]    at org.springframework.data.couchbase.repository.query.AbstractN1qlBasedQuery.executeDependingOnType(AbstractN1qlBasedQuery.java:143) ~[spring-data-couchbase-3.0.9.RELEASE.jar:3.0.9.RELEASE]    at org.springframework.data.couchbase.repository.query.AbstractN1qlBasedQuery.execute(AbstractN1qlBasedQuery.java:106) ~[spring-data-couchbase-3.0.9.RELEASE.jar:3.0.9.RELEASE]    at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.doInvoke(RepositoryFactorySupport.java:590) ~[spring-data-commons-2.0.9.RELEASE.jar:2.0.9.RELEASE]    at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.invoke(RepositoryFactorySupport.java:578) ~[spring-data-commons-2.0.9.RELEASE.jar:2.0.9.RELEASE]    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) ~[spring-aop-5.0.8.RELEASE.jar:5.0.8.RELEASE]我们还尝试将 的返回类型更改deleteAllByName(String name);为void，但结果相同。

Answer 1

据我所知，您必须返回要删除的对象：

@N1qlPrimaryIndexed

@ViewIndexed(designDoc = "maintenanceSchedule")

public interface MaintenanceScheduleRepository extends CouchbasePagingAndSortingRepository<MaintenanceSchedule, String> {

    List<MaintenanceSchedule> deleteByCompanyIdAndMaintenancePlanId(String companyId, String maintenancePlanId);

    List<MaintenanceSchedule> deleteByCompanyIdAndResourceIdAndMaintenancePlanIdIn(String companyId, String resourceId,

                                                                               List<String> maintenancePlanIds);

}

如果不需要删除的对象，最好的方法是直接执行 N1QL 查询。