# What is the format specification for \`datomic.databases\` in the catalog for presto/analytics?

**URL:** <https://forum.datomic.com/t/what-is-the-format-specification-for-datomic-databases-in-the-catalog-for-presto-analytics/1533>\
**Category:** Troubleshooting\
**Created:** [July 23, 2020, 9:19am UTC](https://forum.datomic.com/t/what-is-the-format-specification-for-datomic-databases-in-the-catalog-for-presto-analytics/1533 "2020-07-23T09:19:43Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![pieterbreed](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.datomic.com/pieterbreed/32/550_2.png) [@pieterbreed](https://forum.datomic.com/u/pieterbreed)\
**Post date:** [July 23, 2020, 9:19am UTC](https://forum.datomic.com/t/what-is-the-format-specification-for-datomic-databases-in-the-catalog-for-presto-analytics/1533/1 "2020-07-23T09:19:43Z")

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## What is the format specification for `datomic.databases` in the catalog for presto/analytics?

I’ve been through the on-prem docs for analytics a few times, but I can’t an example of this being specified.

I’ve tried:

```auto
datomic.databases=db_one,other_database_name

```

this fails during presto startup with:

```auto
java.lang.IllegalArgumentException: Don't know how to create ISeq from: clojure.lang.Symbol

```

I’ve tried:

```auto
datomic.databases=["db_one" "other_database_name"]

```

Allows presto to start up, but fails during a query in the client with:

```auto
clojure.lang.ExceptionInfo: Expected string for :db-name

```

If I uncomment the `datomic.databases` line in the catalog, the queries work. I’m trying to expose more metadata for my “GUI-enabled” colleagues.