# ORA-00904 due to adding columns of type "\*\_ORDER"

**URL:** <https://discourse.hibernate.org/t/ora-00904-due-to-adding-columns-of-type-order/9242>\
**Category:** Hibernate ORM\
**Created:** [March 21, 2024, 3:50pm UTC](https://discourse.hibernate.org/t/ora-00904-due-to-adding-columns-of-type-order/9242 "2024-03-21T15:50:52Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![Ralin](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.hibernate.org/ralin/32/3212_2.png) [@Ralin](https://discourse.hibernate.org/u/Ralin)\
**Post date:** [March 21, 2024, 3:50pm UTC](https://discourse.hibernate.org/t/ora-00904-due-to-adding-columns-of-type-order/9242/1 "2024-03-21T15:50:52Z")

</div>

I am upgrading to 6.4 from 5.6 and started getting error ORA-00904 when trying to get a collection from an entity. The collection is declared as follows in the user entity:

```auto
	@OneToMany(mappedBy = "id.userId", cascade = CascadeType.ALL, orphanRemoval = true, fetch = FetchType.LAZY)
	@OrderBy("id.userGroupId")
	@CollectionType(type = datatype.jpa.CustomPersistentListType.class)
	private List<UserGroupUser> groups = new ArrayList<>();

```

When trying to do user.getGroups() hibernate makes a request:

```auto
Hibernate: 
    select
        g1_0.USER_ID,
        g1_0.groups_ORDER,
        g1_0.USR_GRP_ID,
        g1_0.OWNER_FLG,
        g1_0.EXPIRATION_DT,
        g1_0.VERSION 
    from
        SC_USR_GRP_USR g1_0 
    where
        g1_0.USER_ID=? 
    order by
        g1_0.USR_GRP_ID

```

The column `g1_0.groups_ORDER` does not exist and I get ORA-00904. This happens with all collections. I logically suspect that the problem is in the sorting, but I couldn’t find similar errors to figure out what I’m doing wrong.

Could this be occurring because of my CustomPersistentListType? Where should I be paying attention?

---

<div class="post-metadata">

**Author:** ![mbladel](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.hibernate.org/mbladel/32/2128_2.png) [@mbladel](https://discourse.hibernate.org/u/mbladel)\
**Post date:** [March 21, 2024, 4:00pm UTC](https://discourse.hibernate.org/t/ora-00904-due-to-adding-columns-of-type-order/9242/2 "2024-03-21T16:00:51Z")

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Could you please share the code for `CustomPersistentListType.class`? Anyways, I’m guessing the “problem” is you custom type defines `CollectionClassification.LIST` as `getClassification()`, so Hibernate is adding the “\_ORDER” column to preserve the order of elements in the association.

Note that by default `java.util.List` collections in Hibernate have `CollectionClassification.BAG` semantifcs (unordered), unless something different is explicitly specified by `hibernate.mapping.default_list_semantics`.

---

<div class="post-metadata">

**Author:** ![Ralin](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.hibernate.org/ralin/32/3212_2.png) [@Ralin](https://discourse.hibernate.org/u/Ralin)\
**Post date:** [April 11, 2024, 11:37am UTC](https://discourse.hibernate.org/t/ora-00904-due-to-adding-columns-of-type-order/9242/3 "2024-04-11T11:37:00Z")

</div>

You were right, it was a bug of mine related to getClassification()