supabase/apps/docs/content/guides/database/postgres/setup-replication-external.mdx

---
title: 'Replicate to another Postgres database using Logical Replication'
description: 'Example to setup logical replication using publish-subscribe to a Postgres database outside of Supabase'
footerHelpType: 'postgres'
---

For this example, you will need:

- A Supabase project
- A Postgres database (running v10 or newer)

You will be running commands on both of these databases to publish changes from the Supabase database to the external database.

1. Create a `publication` on the **Supabase database**:

```sql
CREATE PUBLICATION example_pub;
```

2. Also on the **Supabase database**, create a `replication slot`:

```sql
select pg_create_logical_replication_slot('example_slot', 'pgoutput');
```

3. Now connect to your **external database** and subscribe to the `publication`

<Admonition type="caution">

This needs a **direct** connection (not a Connection Pooler) to your database and you can find the connection info in the [**Connect** panel](/dashboard/project/_?showConnect=true) in the `Direct connection` section.

You will also need to ensure that IPv6 is supported by your replication destination (or you can enable the [IPv4 add-on](/docs/guides/platform/ipv4-address))

If you would prefer not to use the `postgres` user, then you can run `CREATE ROLE <user> WITH REPLICATION;` using the `postgres` user.

</Admonition>

```sql
CREATE SUBSCRIPTION example_sub
CONNECTION 'host=db.oaguxblfdassqxvvwtfe.supabase.co user=postgres password=YOUR_PASS dbname=postgres'
PUBLICATION example_pub
WITH (copy_data = true, create_slot=false, slot_name=example_slot);
```

<Admonition type="note">

For projects running Postgres 17+, it is possible to subscribe to a [Read
Replica](/docs/guides/platform/read-replicas) by using your Read Replica's connection string.

</Admonition>

<Admonition type="note">

`create_slot` is set to `false` because `slot_name` is provided and the slot was already created in Step 2.
To copy data from before the slot was created, set `copy_data` to `true`.

</Admonition>

4. Now we'll go back to the Supabase DB and add all the tables that you want replicated to the publication.

```sql
ALTER PUBLICATION example_pub ADD TABLE example_table;
```

5. Check the replication status using `pg_stat_replication`

```sql
select * from pg_stat_replication;
```

<Admonition type="note">

You can add more tables to the initial publication, but you're going to need to do a REFRESH on the subscribing database.
See https://www.postgresql.org/docs/current/sql-alterpublication.html

</Admonition>