Spring数据JPA:生成动态查询

https://docs.spring.io/spring-data/jpa/docs/current/reference/html/#query-by-example

示例查询(QBE)是一种用户友好的查询技术 要求您编写包含字段名的查询。实际上,查询 例如,不需要使用 存储特定的查询语言。

定义:

为此,请扩展存储库接口 QueryByExampleExecutor<T>

public interface PersonRepository extends CrudRepository<Person, String>, QueryByExampleExecutor<Person> {
}

QueryByExampleExecutor :

public interface QueryByExampleExecutor<T> {

  <S extends T> S findOne(Example<S> example);

  <S extends T> Iterable<S> findAll(Example<S> example);

  // … more functionality omitted.
}

Example<Person> example = Example.of(new Person("Jon", "Snow"));
repo.findAll(example);


ExampleMatcher matcher = ExampleMatcher.matching().
    .withMatcher("firstname", endsWith())
    .withMatcher("lastname", startsWith().ignoreCase());

Example<Person> example = Example.of(new Person("Jon", "Snow"), matcher); 
repo.count(example);

更多信息

• https://docs.spring.io/spring data/jpa/docs/current/reference/html/#查询-以身作则
• https://github.com/spring-projects/spring-data-examples/tree/master/jpa/query-by-example
• Spring Data JPA: Query by Example?

是的,请看一下QueryDSL对Spring数据的支持。您的用例可以通过谓词实现。简而言之,您必须创建一个谓词,在其中传递非空字段,然后将该谓词传递给以谓词为参数的findAll方法。您的存储库接口还必须扩展querydsldpredicateexecutor