# Filtering and multi-database queries

**URL:** https://forum.datomic.com/t/filtering-and-multi-database-queries/481
**Category:** Client API
**Created:** [June 21, 2018, 1:12pm UTC](https://forum.datomic.com/t/filtering-and-multi-database-queries/481 "2018-06-21T13:12:02Z")
**Posts on this page:** 6
**Page:** 1

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### Author: ![pdkimbrel](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.datomic.com/pdkimbrel/32/201_2.png) [@pdkimbrel](https://forum.datomic.com/u/pdkimbrel)
#### Post date: [June 21, 2018, 1:12pm UTC](https://forum.datomic.com/t/filtering-and-multi-database-queries/481/1 "2018-06-21T13:12:02Z")

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Our current use case heavily uses both the on-premise capabilities of [**filters**](https://docs.datomic.com/on-prem/filters.html) and [**multi-database queries**](https://cjohansen.no/querying-across-datomic-databases/).

We would like to move to Datomic Cloud, so we tried moving to the Client API and it appears to not support either filters or multi-database queries.

Are there any plans, specifically in Datomic Cloud, to support **filters**?

Additionally, any plans to support **multi-database queries**?

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### Author: ![dustingetz](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.datomic.com/dustingetz/32/56_2.png) [@dustingetz](https://forum.datomic.com/u/dustingetz)
#### Post date: [June 21, 2018, 2:21pm UTC](https://forum.datomic.com/t/filtering-and-multi-database-queries/481/2 "2018-06-21T14:21:05Z")

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Cloud supports cross db join, the cloud client d/connect API changed wrt the onprem client API to support this. As for d/filter in Cloud, I am not aware of any statements from Cognitect about d/filter’s future one way or the other.

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### Author: ![terjesb](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.datomic.com/terjesb/32/66_2.png) [@terjesb](https://forum.datomic.com/u/terjesb)
#### Post date: [June 21, 2018, 3:16pm UTC](https://forum.datomic.com/t/filtering-and-multi-database-queries/481/3 "2018-06-21T15:16:11Z")

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Thanks for making me aware of cross-db join in cloud… Perhaps the Datomic team could extend [https://docs.datomic.com/on-prem/clients-and-peers.html](https://docs.datomic.com/on-prem/clients-and-peers.html) with a third column and separate between Peer, On-Prem Client and Cloud Client to make such differences more discoverable?

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### Author: ![dustingetz](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.datomic.com/dustingetz/32/56_2.png) [@dustingetz](https://forum.datomic.com/u/dustingetz)
#### Post date: [June 21, 2018, 5:08pm UTC](https://forum.datomic.com/t/filtering-and-multi-database-queries/481/4 "2018-06-21T17:08:11Z")

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Suggestion for datomic team: perhaps use page background color to distinguish between cloud vs onprem? Like red prod terminals. People google for problems and end up on the wrong page (or are confused as to the way the docs are organized in parallel)

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### Author: ![dustingetz](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.datomic.com/dustingetz/32/56_2.png) [@dustingetz](https://forum.datomic.com/u/dustingetz)
#### Post date: [July 21, 2018, 1:38pm UTC](https://forum.datomic.com/t/filtering-and-multi-database-queries/481/5 "2018-07-21T13:38:21Z")

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@terjesb I was wrong about cross-db join in cloud, i believe it is not enabled right now. It’s my understanding from some informal conversations that the cross-db feature has some implementation difficulties wrt client vs ion.

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### Author: ![adamfeldman](https://avatars.discourse-cdn.com/v4/letter/a/48db29/32.png) [@adamfeldman](https://forum.datomic.com/u/adamfeldman)
#### Post date: [March 24, 2019, 12:27am UTC](https://forum.datomic.com/t/filtering-and-multi-database-queries/481/6 "2019-03-24T00:27:01Z")

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There does seem to be some kind of filters in Cloud: [https://docs.datomic.com/cloud/time/filters.html](https://docs.datomic.com/cloud/time/filters.html)
