使用 @Query 注解实现查询

使用 @Query 注解实现查询



// ------------------------------------ 使用 @Query 注解
// 没有参数的查询
@Query("select p from Person p where p.id = (select max(p2.id) from Person p2)")
Person getMaxIdPerson();

/**
 * 参数名称和参数顺序耦合
 * @param lastName
 * @param email
 * @return
 */
@Query("select p from Person p where lastName=?1 and email=?2")
Person readPersonByLastNameAndEmail(String lastName,String email);

@Query("select p from Person p where email=:email and  lastName=:name")
Person readPersonByLastNameAndEmailThroughName(@Param("name") String lastName,@Param("email") String email);

// 使用 like
@Query("select p from Person p where lastName like ?1")
Person readPersonByLike(String likeName);

// @Query 注解支持使用百分号
@Query("select p from Person p where lastName like %?1%")
Person readPersonByLike2(String likeName);

// @Query 注解支持使用百分号
@Query("select p from Person p where lastName like %:lastName%")
Person readPersonByLike3(@Param("lastName")String name);

// 使用原生的 SQL
@Query(value="select * from jpa_person p1 where p1.last_name like %:lastName%",nativeQuery=true)
Person getPersonUsingOriginSQL(@Param("lastName")String lastName);
测试代码：

// 以下测试 @Query 注解
@Test
public void testQueryAnnotationWithoutParam(){
    Person person = personRepository.getMaxIdPerson();
    System.out.println(person);
}

@Test
public void testQueryAnnotationWithParam(){
    Person person = personRepository.readPersonByLastNameAndEmail("liwei","liwei@sina.com");
    System.out.println(person);
}

@Test
public void testQueryAnnotationWithParamThroughName(){
    Person person = personRepository.readPersonByLastNameAndEmailThroughName("zhouguang","zhouguang@163.com");
    System.out.println(person);
}

@Test
public void testQueryAnnotationWithParamThroughLike(){
    Person person = personRepository.readPersonByLike("%zhou%");
    System.out.println(person);
}

@Test
public void testQueryAnnotationWithParamThroughLike2(){
    Person person = personRepository.readPersonByLike2("hu");
    System.out.println(person);
}

@Test
public void testQueryAnnotationWithParamThroughLike3(){
    Person person = personRepository.readPersonByLike3("wei");
    System.out.println(person);
}

@Test
public void testQueryAnnotationWithParamThroughLike4(){
    Person person = personRepository.getPersonUsingOriginSQL("wei");
    System.out.println(person);
}
注意到：如果我们使用原生的 SQL，控制台打印的语句也会是原生 SQL 的，例如上面我们最后一个测试方法控制台打印：

这里写图片描述

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