Receive replicated data in another Neon database
Cross-region or cross-project data movement
Neon · Const
Subscriber
In Neon logical replication, a subscriber is the destination database or platform that receives an initial data copy from a publisher and then ongoing row-level changes through a subscription.
How it works
In Neon logical replication, a subscriber is the destination database or platform. It initially receives a copy of the publisher's data, then receives subsequent changes through a subscription, which connects to the publisher and identifies the publication to consume.
Syntax
CREATE SUBSCRIPTION subscription_name CONNECTION 'connection_string' PUBLICATION publication_name;Parameters
| Name | Type | Description |
|---|---|---|
subscription_name | identifier | Unique name assigned to the subscription. |
CONNECTION | connection string | Connection string for the publisher database. |
PUBLICATION | publication name | Publication whose changes the subscriber receives. |
Returns
No value; it creates a subscription that receives replicated data.
Key points
- The subscriber is the receiving side of a publisher–subscriber replication arrangement.
- Initial synchronization copies the publisher's existing data to the subscriber.
- After synchronization, changes made at the publisher are streamed to the subscriber.
- The subscriber uses a subscription as its downstream replication configuration.
- The subscription both connects to the source and selects the publication to consume.
- Subscription setup requires unique naming, publisher credentials, a connection string, and a publication name.
Common mistakes
- Use a direct publisher connection rather than a pooled connection; the replication connection must remain persistent.
Example: Create a PostgreSQL subscription
CREATE SUBSCRIPTION my_subscription
CONNECTION 'postgresql://username:password@host:port/dbname'
PUBLICATION my_publication;Creates a subscription on the destination database that connects to a publisher and receives the publication's replicated data.
When to use it
Use Neon as the replication destination
Migration from an external PostgreSQL provider
Consume publisher changes in real time
Continuous downstream data synchronization
Interview questions
QWhat is a subscriber in Neon logical replication?
A subscriber is the downstream database or platform that receives replicated data. It first receives an initial copy, then receives later changes from the publisher through a subscription.
Follow-up: What identifies the data flow? A subscription connects to the publisher and names the publication whose changes it should receive.
QHow do you configure a subscriber?
Create a subscription on the destination database with CREATE SUBSCRIPTION. The statement supplies a unique subscription name, a connection string for the publisher, and the publication name.
Follow-up: What must the connection string target? It must use the publisher's direct database connection rather than a pooled endpoint.
QWhat are the main replication boundaries for a subscriber?
Logical replication transfers row-level data changes, including inserts, updates, deletes, and truncates, but it does not replicate DDL. Therefore, schema changes must be applied and coordinated separately.
Follow-up: For an additive schema change, which side changes first? Apply it on the subscriber before applying it on the publisher.
Related
publisherpublicationsubscriptionCREATE SUBSCRIPTIONpg_stat_subscriptionlogical replication