PostgreSQL table function

BETA

¶

The Tinybird postgresql() table function allows you to read data from your existing PostgreSQL database into Tinybird, then schedule a regular copy pipe to orchestrate synchronization. You can load full tables, and every run performs a full replace on the data source.

To use it, define a node using standard SQL and the postgresql function keyword, then publish the node as a copy pipe that does a sync on every run. See Table functions for general information and tips.

Setting secrets¶

Table functions require authentication credentials (such as AWS keys) that must be stored securely. Tinybird provides different methods for managing secrets depending on the version you're using.

Using the Variables API (Classic)¶

In Tinybird Classic, you must set your credentials using the Environment Variables API:

curl -X POST -H "Authorization: Bearer $TOKEN" \
  --data-urlencode "name=pg_username" \
  --data-urlencode "value=postgres" \
  https://<TB_HOST_URL>/v0/variables/

For more details, see the Environment Variables API documentation.

Using the CLI (Forward)¶

In Tinybird Forward, you manage secrets using the tb secret command:

tb secret set pg_username postgres
tb secret set pg_password your_password

For more details, see the tb secret command documentation.

Once you've set up your secrets, you can reference them in your SQL with the tb_secret function as shown in the Syntax section below.

Syntax¶

Create a new copy pipe node. Call the postgresql table function and pass the hostname and port, database, table, user, and password:

SELECT *
FROM postgresql(
  'aws-0-eu-central-1.TODO.com:3866',
  '<YOUR_PG_DB>',
  '<YOUR_PG_TABLE>',
  {{tb_secret('pg_username')}},
  {{tb_secret('pg_password')}}
)

TYPE COPY
TARGET_DATASOURCE pg_copy_target_ds

Publish this node as a copy pipe. You can choose to append only new data or replace all data.

Type support and inference¶

Here's a detailed conversion table:

Enabling the PostgreSQL Table Function¶

In Production¶

To enable the PostgreSQL table function in your production workspace, please contact Tinybird support. They will enable the function for your specific workspace.

For Local Development (Forward only)¶

After the feature is enabled for your Workspace, it becomes available for local development automatically. You do not need to take any extra steps to enable it for local use.

Using the PostgreSQL Table Function Locally (Forward only)¶

There are two primary scenarios for connecting to a PostgreSQL database from Tinybird Local:

Connecting to PostgreSQL Running on Your Host Machine¶

When connecting to PostgreSQL running directly on your local machine (not in a container), keep the following considerations in mind:

1. Network Connection: The connection to your PostgreSQL server originates from within the Tinybird Local container (Docker or where you're running Tinybird Local).
2. Server Reachability: Ensure your PostgreSQL server is reachable from inside the Docker network.
3. Credentials: You must set the secrets for your PostgreSQL credentials in your local Tinybird project. See the tb secret documentation for details. You can provide default values for these credentials, but note that defaults can only be defined inside the pipe SQL itself—not through the CLI. You can set your credentials using:

tb secret set pg_username <YOUR_PG_USERNAME>
tb secret set pg_password <YOUR_PG_PASSWORD>

4. Server Address: Use the container-reachable address in your queries, not localhost.

Example query:

NODE get_ids
SQL >
%
SELECT id
FROM postgresql(
 'host.docker.internal:5432',
  '<YOUR_PG_DB>',
  '<YOUR_PG_TABLE>',
  {{ tb_secret('pg_username', '<YOUR_DEFAULT_USERNAME>') }},
  {{ tb_secret('pg_password', '<YOUR_DEFAULT_PWD>') }}
)

TYPE COPY
TARGET_DATASOURCE pg_copy_target_ds

Connecting to PostgreSQL Running in a Docker Container¶

When connecting to a PostgreSQL container running in Docker, follow these steps to set up network communication between Tinybird Local and your PostgreSQL container:

1. Create a shared Docker network for PostgreSQL and Tinybird Local to communicate:

docker network create tbnet

2. Run PostgreSQL container in the shared network:

docker run --name local-postgres \
  --network tbnet \
  -e POSTGRES_USER=tb_user \
  -e POSTGRES_PASSWORD=tb_pass \
  -e POSTGRES_DB=test_db \
  -p 5432:5432 \
  -d postgres:15

3. Connect Tinybird Local to the shared network:

docker network connect tbnet tinybird-local

4. Verify network connectivity by checking that both containers are on the same network. The NetworkID, Gateway, and IPAddress values should match:

docker inspect tinybird-local --format '{{json .NetworkSettings.Networks}}' | jq
docker inspect local-postgres --format '{{json .NetworkSettings.Networks}}' | jq

5. Set secrets in Tinybird Local to match your PostgreSQL container configuration:

tb secret set pg_username tb_user
tb secret set pg_password tb_pass

6. Update the PostgreSQL host in your query to use the container name as the hostname:

NODE get_ids
SQL >
%
SELECT id
FROM postgresql(
  'local-postgres:5432',  -- Use container name as hostname
  '<YOUR_PG_DB>',
  '<YOUR_PG_TABLE>',
  {{ tb_secret('pg_username') }},
  {{ tb_secret('pg_password') }}
)

TYPE COPY
TARGET_DATASOURCE pg_copy_target_ds

7. Build and deploy your pipe:

tb build
tb deploy

8. Test that the connection works You can run the copy pipe with tb copy run <pipe_name> to ensure Postgres data lands in the target Data Source.

Considerations¶

The following considerations apply to the postgresql() table function:

• Tinybird doesn't support all PostgreSQL types directly, so some types are mapped to String, which is the most flexible type for arbitrary data.
• For the NUMERIC and DECIMAL types, Decimal(p, s) in Tinybird requires specifying precision (p) and scale (s).
• Time zone support in Tinybird's DateTime can be managed via additional functions or by ensuring consistent storage and retrieval time zones.
• Some types like INTERVAL don't have a direct equivalent in Tinybird and are usually stored as String or decomposed into separate fields.

See also¶

• Table functions