# Datomic Cloud **URL:** https://forum.datomic.com/c/datomic-cloud/12.md [Latest](https://forum.datomic.com/latest.md) · [Categories](https://forum.datomic.com/categories.md) --- ## [About the Datomic Cloud category](https://forum.datomic.com/t/about-the-datomic-cloud-category/95)
**Author:** [@jaret](https://forum.datomic.com/u/jaret)\ **Replies:** 0\ **Last updated:** [July 31, 2017, 4:20pm UTC](https://forum.datomic.com/t/about-the-datomic-cloud-category/95 "2017-07-31T16:20:49Z")
Discussion of Datomic Cloud Datomic Cloud is a distributed database that provides ACID transactions, a flexible schema, powerful Datalog queries, complete data history, high availability, horizontal scaling, and integra… --- ## [Idle databases spun down after 24h on Datomic Cloud cause "Loading database" on the next transaction](https://forum.datomic.com/t/idle-databases-spun-down-after-24h-on-datomic-cloud-cause-loading-database-on-the-next-transaction/2653)
**Author:** [@onetom](https://forum.datomic.com/u/onetom)\ **Replies:** 2\ **Last updated:** [October 6, 2026, 2:48pm UTC](https://forum.datomic.com/t/idle-databases-spun-down-after-24h-on-datomic-cloud-cause-loading-database-on-the-next-transaction/2653 "2026-10-06T14:48:00Z")
Setup Datomic Cloud 1254-9433, production topology, us-west-2. Primary compute group api2: 2 x i3.2xlarge. Query group web: 1-3 x i3.xlarge. About 14 databases. PreloadDb is empty on both groups. Ions use the in-proces… --- ## [\`d/client\` does network access](https://forum.datomic.com/t/d-client-does-network-access/2376)
**Author:** [@onetom](https://forum.datomic.com/u/onetom)\ **Replies:** 2\ **Last updated:** [July 1, 2026, 7:41am UTC](https://forum.datomic.com/t/d-client-does-network-access/2376 "2026-07-01T07:41:29Z")
According to datomic.client.api documentation : This function does not communicate with a server and returns immediately. However, I do get exceptions quite often lately on d/client calls, which are delayed by a few … --- ## [Ion push trying to read non-existent maven artifact](https://forum.datomic.com/t/ion-push-trying-to-read-non-existent-maven-artifact/2627)
**Author:** [@wevrem](https://forum.datomic.com/u/wevrem)\ **Replies:** 6\ **Last updated:** [May 20, 2026, 10:29pm UTC](https://forum.datomic.com/t/ion-push-trying-to-read-non-existent-maven-artifact/2627 "2026-05-20T22:29:20Z")
Attempting to push an ion and I get an error about not finding artifact ion-1.0.47.jar. I found a similar issue with @charliekilo having trouble with version 0.9.7. I tried the steps that @jaret suggested, and I can succ… --- ## [How are people handling disaster recovery?](https://forum.datomic.com/t/how-are-people-handling-disaster-recovery/1984)
**Author:** [@DanM](https://forum.datomic.com/u/DanM)\ **Replies:** 3\ **Last updated:** [October 20, 2025, 9:06am UTC](https://forum.datomic.com/t/how-are-people-handling-disaster-recovery/1984 "2025-10-20T09:06:16Z")
I was looking at ways to back up Datomic Cloud, and found Cloud backups & recovery - #13 by lukenelson, which is various people asking for it and the reponse being “It uses S3 and DynamoDB, both of which have very high d… --- ## [\`Loading database\` exception](https://forum.datomic.com/t/loading-database-exception/2382)
**Author:** [@onetom](https://forum.datomic.com/u/onetom)\ **Replies:** 4\ **Last updated:** [July 16, 2025, 4:15pm UTC](https://forum.datomic.com/t/loading-database-exception/2382 "2025-07-16T16:15:33Z")
We are getting this exception more and more often on d/db calls, even on a freshly provisioned Datomic Cloud system, using the latest CF templates and almost latest Clojure libs (the versions before the 2024 Feb 12 relea… --- ## [Is it safe to upgrade \`clojure.core.{async,memoize,cache}\` as of 2025-05-09?](https://forum.datomic.com/t/is-it-safe-to-upgrade-clojure-core-async-memoize-cache-as-of-2025-05-09/2560)
**Author:** [@onetom](https://forum.datomic.com/u/onetom)\ **Replies:** 5\ **Last updated:** [June 23, 2025, 11:35am UTC](https://forum.datomic.com/t/is-it-safe-to-upgrade-clojure-core-async-memoize-cache-as-of-2025-05-09/2560 "2025-06-23T11:35:52Z")
Most recent Datomic Cloud ion servers seems to use the following versions of the libraries in question: org.clojure/core.async #:mvn{:version "1.6.681"}, org.clojure/core.cache #:mvn{:version "1.0.225"}, org.cl… --- ## [Datomic Cloud Query Speed](https://forum.datomic.com/t/datomic-cloud-query-speed/2551)
**Author:** [@maniginam](https://forum.datomic.com/u/maniginam)\ **Replies:** 1\ **Last updated:** [March 19, 2025, 4:03pm UTC](https://forum.datomic.com/t/datomic-cloud-query-speed/2551 "2025-03-19T16:03:33Z")
We recently went from datomic pro to datomic cloud. The queries that included where-clauses that worked in pro are not working in cloud due to regex, but even the ones that are pulling all of one entity without any wher… --- ## [Does Datomic local respect noHistory](https://forum.datomic.com/t/does-datomic-local-respect-nohistory/2402)
**Author:** [@shashurup](https://forum.datomic.com/u/shashurup)\ **Replies:** 3\ **Last updated:** [September 11, 2024, 1:03pm UTC](https://forum.datomic.com/t/does-datomic-local-respect-nohistory/2402 "2024-09-11T13:03:48Z")
I use Datomic local for not so large database with some high churn attributes marked with noHistory. I hadn’t been noticing degrading performance until I bumped some dependencies and deployed a new version of my app. Fo… --- ## [Best practice for hosting/deploying datomic-cloud/ions to AWS Control Tower accounts](https://forum.datomic.com/t/best-practice-for-hosting-deploying-datomic-cloud-ions-to-aws-control-tower-accounts/2090)
**Author:** [@pieterbreed](https://forum.datomic.com/u/pieterbreed)\ **Replies:** 8\ **Last updated:** [July 29, 2024, 5:16am UTC](https://forum.datomic.com/t/best-practice-for-hosting-deploying-datomic-cloud-ions-to-aws-control-tower-accounts/2090 "2024-07-29T05:16:41Z")
Hi All, I’m looking for some guidance or advice or even “here’s the RTFM link”. We have a new AWS account which is being management by AWS Control Tower. In the AWS best practice guidance documents, they recommend that… --- ## [Transaction Function Exceptions](https://forum.datomic.com/t/transaction-function-exceptions/2428)
**Author:** [@potetm](https://forum.datomic.com/u/potetm)\ **Replies:** 1\ **Last updated:** [July 21, 2024, 3:36pm UTC](https://forum.datomic.com/t/transaction-function-exceptions/2428 "2024-07-21T15:36:12Z")
I’m getting an exception inside of a transaction function, but I’m not seeing any CloudWatch Logs with the exception in it. Is there something we can search for to find exceptions from transaction functions? --- ## [\`:db/ensure\` doesn't seem virtual](https://forum.datomic.com/t/db-ensure-doesnt-seem-virtual/2296)
**Author:** [@onetom](https://forum.datomic.com/u/onetom)\ **Replies:** 4\ **Last updated:** [July 17, 2024, 1:52pm UTC](https://forum.datomic.com/t/db-ensure-doesnt-seem-virtual/2296 "2024-07-17T13:52:58Z")
I just tried using :db/ensure, but when I pull the entity, which I’ve transacted with a :db/ensure attribute, I did get back that :db/ensure attribute. (ns xxx (:require \[datomic.client.api :as d\] \[clojure… --- ## [Overwhelmed query group, so can I issue transactions directly to the compute group?](https://forum.datomic.com/t/overwhelmed-query-group-so-can-i-issue-transactions-directly-to-the-compute-group/2405)
**Author:** [@mharris](https://forum.datomic.com/u/mharris)\ **Replies:** 1\ **Last updated:** [May 15, 2024, 3:31am UTC](https://forum.datomic.com/t/overwhelmed-query-group-so-can-i-issue-transactions-directly-to-the-compute-group/2405 "2024-05-15T03:31:55Z")
A batch processing job ran into an issue where it overwhelmed it’s query group. It was processing large queries with an occasional transact on too many threads. The datomic instance was pegged to 100% CPU usage, so it’s … --- ## [Message Listeners in Ions](https://forum.datomic.com/t/message-listeners-in-ions/860)
**Author:** [@okocim](https://forum.datomic.com/u/okocim)\ **Replies:** 8\ **Last updated:** [March 5, 2024, 3:20am UTC](https://forum.datomic.com/t/message-listeners-in-ions/860 "2024-03-05T03:20:41Z")
If I have an SQS message listener that I need to run for async processing, is there any way I can start this from within the nodes on a compute group, or do I always have to invoke a lambda from the outside to do such a … --- ## [Ion push :repl-cmd](https://forum.datomic.com/t/ion-push-repl-cmd/2369)
**Author:** [@itaied](https://forum.datomic.com/u/itaied)\ **Replies:** 0\ **Last updated:** [January 11, 2024, 6:45pm UTC](https://forum.datomic.com/t/ion-push-repl-cmd/2369 "2024-01-11T18:45:04Z")
Hello, I’m trying to separate my prod and dev envs. I have 2 configs for the client that I want to load to the classpath depending on the env. As a default, load config/dev/app/config.edn and for prod alias, load conf… --- ## [Datomic cloud failure on import-cloud](https://forum.datomic.com/t/datomic-cloud-failure-on-import-cloud/2366)
**Author:** [@itaied](https://forum.datomic.com/u/itaied)\ **Replies:** 2\ **Last updated:** [January 10, 2024, 8:05am UTC](https://forum.datomic.com/t/datomic-cloud-failure-on-import-cloud/2366 "2024-01-10T08:05:06Z")
hey all I’m trying to run import-cloud but it fails with the error: ; Execution error (IllegalArgumentException) at datomic.dev-local.impl/fn (impl.clj:493). ; This client does not support dev-local import. My setup i… --- ## [Data export / import](https://forum.datomic.com/t/data-export-import/979)
**Author:** [@eraad](https://forum.datomic.com/u/eraad)\ **Replies:** 2\ **Last updated:** [November 1, 2023, 7:00pm UTC](https://forum.datomic.com/t/data-export-import/979 "2023-11-01T19:00:58Z")
Hi, we want to change our production Datomic Cloud system name. Since the only way is to create a new system, we are exploring ways to transfer data from the ugly-name system to our newly cool-named system. Our work pla… --- ## [Is it possible to extend ion.cast/event, alert format](https://forum.datomic.com/t/is-it-possible-to-extend-ion-cast-event-alert-format/2332)
**Author:** [@eoliphant](https://forum.datomic.com/u/eoliphant)\ **Replies:** 0\ **Last updated:** [October 19, 2023, 3:54pm UTC](https://forum.datomic.com/t/is-it-possible-to-extend-ion-cast-event-alert-format/2332 "2023-10-19T15:54:59Z")
Hi, we’ve wired up our cloud instances with the open telemetry agent and it’s working quite well. One thing we want to add now is the trace/span id to log messages. with log4j/etc it’s just a matter updating the log fo… --- ## [AWS Free Tier limit alert](https://forum.datomic.com/t/aws-free-tier-limit-alert/2302)
**Author:** [@danbunea](https://forum.datomic.com/u/danbunea)\ **Replies:** 3\ **Last updated:** [August 29, 2023, 11:42am UTC](https://forum.datomic.com/t/aws-free-tier-limit-alert/2302 "2023-08-29T11:42:12Z")
I have a Datomic Ions - production, without very much data in in. A few tens of thousands of datoms. I keep receiving from AWS warnings about read capacity. I will attach 2 screenshots of the alarm. I really don’… --- ## [Intermittently seeing UnableToForward anomaly](https://forum.datomic.com/t/intermittently-seeing-unabletoforward-anomaly/2315)
**Author:** [@bringe](https://forum.datomic.com/u/bringe)\ **Replies:** 3\ **Last updated:** [August 23, 2023, 4:11pm UTC](https://forum.datomic.com/t/intermittently-seeing-unabletoforward-anomaly/2315 "2023-08-23T16:11:48Z")
At my company we’ve been intermittently seeing anomalies with the message “UnableToForward” since around March of this year. There’s no apparent problem, but I’m wondering if we can get more info on what this might be fr… --- ## [Where to look in AWS when deploy (not push) fails?](https://forum.datomic.com/t/where-to-look-in-aws-when-deploy-not-push-fails/729)
**Author:** [@vvvvalvalval](https://forum.datomic.com/u/vvvvalvalval)\ **Replies:** 9\ **Last updated:** [August 1, 2023, 3:40pm UTC](https://forum.datomic.com/t/where-to-look-in-aws-when-deploy-not-push-fails/729 "2023-08-01T15:40:07Z")
So, after pushing then running the deploy-status command for about 2 minutes, I got the dreaded {:deploy-status "FAILED", :code-deploy-status "FAILED"}. Where can I go from there? I’d look in Cloudwatch logs, but there … --- ## [\`(pull $db ?entity pattern)\` is undocumented](https://forum.datomic.com/t/pull-db-entity-pattern-is-undocumented/2299)
**Author:** [@onetom](https://forum.datomic.com/u/onetom)\ **Replies:** 1\ **Last updated:** [July 15, 2023, 4:56am UTC](https://forum.datomic.com/t/pull-db-entity-pattern-is-undocumented/2299 "2023-07-15T04:56:28Z")
It is possible to supply a src-var argument to a pull function within a Datalog query (as demonstrated below), though the documentation only mentions the 2 arity variant: pull-expr = \[‘pull’ variable p… --- ## [Multi-tenancy](https://forum.datomic.com/t/multi-tenancy/2298)
**Author:** [@onetom](https://forum.datomic.com/u/onetom)\ **Replies:** 1\ **Last updated:** [July 15, 2023, 2:16am UTC](https://forum.datomic.com/t/multi-tenancy/2298 "2023-07-15T02:16:05Z")
Kenny Williams wrote a great article on this topic: Since he has no comment capabilities on his website, I thought we can use this forum for discussions about it. Personally, I would be interested to know what is the … --- ## [Testing Setups?](https://forum.datomic.com/t/testing-setups/1478)
**Author:** [@lucasjordan](https://forum.datomic.com/u/lucasjordan)\ **Replies:** 2\ **Last updated:** [June 8, 2020, 2:52pm UTC](https://forum.datomic.com/t/testing-setups/1478 "2020-06-08T14:52:17Z")
Greetings, I am new to all this, but I have watched a ton of videos, so please forgive my ignorance… I am working from the ions-starter project, and have it setup and working. I am now trying to figure out the best pra… --- ## [LoadIonsFailed caused by StackOverflowError in clj-antlr](https://forum.datomic.com/t/loadionsfailed-caused-by-stackoverflowerror-in-clj-antlr/747)
**Author:** [@vvvvalvalval](https://forum.datomic.com/u/vvvvalvalval)\ **Replies:** 3\ **Last updated:** [February 27, 2019, 3:39pm UTC](https://forum.datomic.com/t/loadionsfailed-caused-by-stackoverflowerror-in-clj-antlr/747 "2019-02-27T15:39:46Z")
I’m getting a very mysterious error that seems related to my deployments failing randomly (I’m saying randomly because application versions which used to be loaded successfully now fail). What’s strange is that I’m gett… --- ## [Idiomatic pagination using latest features](https://forum.datomic.com/t/idiomatic-pagination-using-latest-features/1454)
**Author:** [@steve.nextdoc](https://forum.datomic.com/u/steve.nextdoc)\ **Replies:** 9\ **Last updated:** [June 6, 2023, 1:59pm UTC](https://forum.datomic.com/t/idiomatic-pagination-using-latest-features/1454 "2023-06-06T13:59:56Z")
With this new release, what is the idiomatic way to do sorted query with pagination? It seems like index-pull is the answer but I wonder if there’s a way to do pagination with qseq? That would be more flexible (in term… --- ## [Annotation using "datomic.tx" issue](https://forum.datomic.com/t/annotation-using-datomic-tx-issue/2202)
**Author:** [@danbunea](https://forum.datomic.com/u/danbunea)\ **Replies:** 13\ **Last updated:** [May 1, 2023, 5:26am UTC](https://forum.datomic.com/t/annotation-using-datomic-tx-issue/2202 "2023-05-01T05:26:04Z")
Hi, I am a newbie and a bit confused about “datomic.tx”. For instance, I am transacting: \[\[:db/add "datomic.tx" :user/id #uuid "19fb47da-3246-4cfe-924e-de0388e75352"\] \[:db/retract 101155069759981 :demo.sales1.product/… --- ## [Large Number of Database](https://forum.datomic.com/t/large-number-of-database/1038)
**Author:** [@tony.kay](https://forum.datomic.com/u/tony.kay)\ **Replies:** 2\ **Last updated:** [April 5, 2023, 11:30am UTC](https://forum.datomic.com/t/large-number-of-database/1038 "2023-04-05T11:30:31Z")
I’ve read the Multi-tenancy & databases thread, but it didn’t quite answer my specific question. I’ve got an application that needs to scale to millions of users. Each user will be creating one or more “environments” t… --- ## [Lookup Ref is interpreted as a tempid String, resulting in "tempid \_ used only as value in transaction"](https://forum.datomic.com/t/lookup-ref-is-interpreted-as-a-tempid-string-resulting-in-tempid-used-only-as-value-in-transaction/2162)
**Author:** [@mlimotte](https://forum.datomic.com/u/mlimotte)\ **Replies:** 2\ **Last updated:** [February 28, 2023, 4:05pm UTC](https://forum.datomic.com/t/lookup-ref-is-interpreted-as-a-tempid-string-resulting-in-tempid-used-only-as-value-in-transaction/2162 "2023-02-28T16:05:09Z")
I’d like to use a Lookup Ref as the identifier for a ref in a new entity transaction. But datomic thinks the ref is a “tempid” string rather than recognizing it as a lookup ref. Here is a sample transaction: (d/transa… --- ## [Upsert behavior with composite tuple key](https://forum.datomic.com/t/upsert-behavior-with-composite-tuple-key/1075)
**Author:** [@jacob](https://forum.datomic.com/u/jacob)\ **Replies:** 5\ **Last updated:** [January 6, 2023, 9:25pm UTC](https://forum.datomic.com/t/upsert-behavior-with-composite-tuple-key/1075 "2023-01-06T21:25:40Z")
Although the composite tuple key does get added on the second transaction, the third transaction fails. A transacted entity won’t actually resolve to an existing entity unless I specify the :foo+bar key explicitly, which… [Next page](https://forum.datomic.com/c/datomic-cloud/12.md?page=1)