> For the complete documentation index, see [llms.txt](https://doc.duaer.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc.duaer.com/integrations/builtin/app-nodes/n8n-nodes-base.postgres.md).

# Use Postgres Trigger in Duaer

Use Postgres Trigger in a Duaer digital organization to call that service. Save the connection under Credentials, then pick a resource and operation on the node. Node note: Listens to Postgres messages
## Postgres Trigger in Duaer

Postgres Trigger is an app node in Duaer for calling that service’s API from a digital organization.

The product’s node note is: Listens to Postgres messages.

## Credentials and parameters

Credential notes are under [Postgres Trigger credentials](/integrations/builtin/credentials/postgres.md).

Parameters accept expressions. Tool parameters that an AI Agent should fill use $fromAI. When a run fails, read the error on the node output first.
## Questions

### How do you add Postgres Trigger to a Duaer digital organization?

Open the node panel on the Duaer canvas, search for Postgres Trigger, and drop it onto the digital organization. Connect it after a trigger or a previous node. If auth is required, save the credential first and select it on the node.

### What should you check first when Postgres Trigger fails in Duaer?

Read the error text on that node’s output, then confirm the credential still works and required parameters are filled. For app nodes, also check permissions and quota on the provider side.