Spring的QueryByExampleExecutor是Spring Data JPA提供的一个接口,用于根据Example对象进行查询。它可以用于投影查询,即只返回部分字段的查询结果。 QueryByExampleExecutor接口提供了以下方法: <T> Optional<T> findOne(Example<S> example):根据Example对象查询单个
{returnrecRepo.findOne(id)}funnewRecored(rec:Record){recRepo.save(rec)}} qbeRecord方法就是Query By Example 的使用例子
@Test publicvoidqueryByExample() { System.out.println("\nFind the Department with the name 'Humanities' \n"+ departmentRepository.findOne(Example.of(newDepartment("Humanities",null))); System.out.println("\nFind Departments with the first name of the chair is 'John'"); departmentRepository....
1.2 QueryByExampleExecutor接口 publicinterfaceQueryByExampleExecutor<T>{// 根据实体查询条件、查找一个对象<SextendsT>Optional<S>findOne(Example<S>example);// 根据实体查询条件、查询一批对象<SextendsT>Iterable<S>findAll(Example<S>example);// 根据实体查询条件并排序、查询一批对象<SextendsT>Iterable<S...
首先,我们来看看 Spring Data的 JpaRepository 接口。我们可以看到它扩展了QueryByExampleExecutor接口以支持查询示例: publicinterfaceJpaRepository<T, ID> extendsPagingAndSortingRepository<T, ID>, QueryByExampleExecutor<T> {} 这个接口引入了 我们从Spring Data熟悉的find()方法的更多变体。但是,每个方法也接受Exa...
【SpringBoot JPA】Query by Example用法,一、参考资料https://docs.spring.io/spring-data/jpa/docs/2.4.11/reference/html/#query-by-example
In this article, we are going to see how the Spring Data JPA Query By Example (QBE) feature works, when you should use it, and what limitations it has.While Spring Data JPA already provides a wide range of options to query data:
import org.springframework.data.repository.query.QueryByExampleExecutor; import org.springframework.stereotype.Repository; @Repository public interface CityRepository extends CrudRepository<City, Long>, QueryByExampleExecutor<City> { } We enable the QBE API by extending our repository from theQueryByExample...
Leave a Comment/Articles,MicroService,r2dbc,Reactive Programming,Spring,Spring Boot,Spring Data,Spring WebFlux/ ByvIns/August 12, 2021 Overview: In this tutorial, I would like to show you theR2DBC Query By ExampleAPI withSpring WebFluxand how we can use this to search for records without expo...
spring data mongo queryByExample maven依赖 <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.4.1.RELEASE</version> <relativePath/> <!-- lookup parent from repository -->