# How do you deal with missing dimensions for foreign keys?

**URL:** <https://discourse.getdbt.com/t/how-do-you-deal-with-missing-dimensions-for-foreign-keys/1274>\
**Category:** In-Depth Discussions\
**Created:** [June 15, 2020, 5:57pm UTC](https://discourse.getdbt.com/t/how-do-you-deal-with-missing-dimensions-for-foreign-keys/1274 "2020-06-15T17:57:15Z")\
**Posts on this page:** 1\
**Showing post:** 5

<div class="post-metadata">

**Author:** ![fabrice.etanchaud](https://sea2.discourse-cdn.com/flex020/user_avatar/discourse.getdbt.com/fabrice.etanchaud/32/595_2.png) [@fabrice.etanchaud](https://discourse.getdbt.com/u/fabrice.etanchaud)\
**Post date:** [June 22, 2020, 4:38pm UTC](https://discourse.getdbt.com/t/how-do-you-deal-with-missing-dimensions-for-foreign-keys/1274/5 "2020-06-22T16:38:19Z")

</div>

Hi @Kimcha, there is an interesting article from Roleant Vos on the subject (in the data vault realm) : [unknown-keys-zero-keys-or-ghost-keys-in-hubs-for-dv2-0](http://roelantvos.com/blog/unknown-keys-zero-keys-or-ghost-keys-in-hubs-for-dv2-0/), with a taxonomy on missing values. In my case, we use two distinct missing key values : one when the key is missing but mandatory (problem in the loading or in source data), and another when the key is missing but optional (loading and data ok but data is missing for ‘business’ reason).

Best,  
Fabrice

---

_[View the full topic](https://discourse.getdbt.com/t/how-do-you-deal-with-missing-dimensions-for-foreign-keys/1274)._