问题描述
我有一个非常简单的查询,它根据in"子句检索值.作为in"参数出现的列表被适当地排序.
I have a pretty simple query which retrieves values base on "in" clause. List that comes as "in" argument is appropriately sorted.
查询:
@Query(value = "select i from ItemEntity i where i.secondaryId in :ids") List<ItemEntity> itemsIn(@Param("ids") List<UUID> ids, Pageable pageable);
我需要以与 List<UUID> 相同的方式对结果进行排序.ids,是否有可能在没有普通 sql 的情况下实现这一点,但只能在 Spring Data 和/或 Hibernate 的帮助下实现.
I need results to be ordered the same way as List<UUID> ids, is it possible to achieve this without plain sql but only with the help of Spring Data and/or Hibernate.
推荐答案
你也可以通过 JPA 做到这一点,但你必须按照你想要的顺序创建一个逗号分隔的 id 列表.在您的情况下,您可以保持相同的顺序.
You can do that by JPA too but you will have to create a comma separated list of ids in the order you want. In your case you can keep same order.
@Query(value = "select i from ItemEntity i where i.secondaryId in :ids order by FIND_IN_SET(i.secondaryId, :idStr)") List<ItemEntity> itemsIn(@Param("ids") List<UUID> ids, @Param("idStr") String idStr);
要创建逗号分隔列表,您可以使用 java 8 流:
To create comma separated list you can java 8 stream:
ids.stream().map(Object::toString).collect(Collectors.joining(","));
例子:
SELECT id FROM User WHERE id in (2,3,1) ORDER BY FIND_IN_SET(id,"2,3,1");
结果:
+----+ | id | +----+ | 2 | | 3 | | 1 | +----+
还有一种使用 JPQL 的替代方法:
There is also one alternative using JPQL:
You can use ,,FIELD'' instead of ,,FIND_IN_SET ''.
您可以在此处找到示例:https://stackoverflow.com/a/65943906/15101302
You can find the example here: https://stackoverflow.com/a/65943906/15101302