Convert PostgreSQL Table to CSV

This n8n workflow provides a simple, manual way to extract data from a PostgreSQL database and convert it into a spreadsheet file (like CSV). It's ideal for quick data exports or generating reports from your database without writing custom scripts.

What it does

This workflow performs the following steps:

1. Manual Trigger: The workflow starts when you manually click 'Execute workflow' in the n8n editor.
2. Query PostgreSQL: It connects to a configured PostgreSQL database and executes a query to retrieve data.
3. Edit Fields: The retrieved data is then passed to an "Edit Fields (Set)" node, allowing for potential transformation or selection of specific fields before conversion.
4. Convert to Spreadsheet File: Finally, the processed data is converted into a spreadsheet file format (e.g., CSV) which can then be downloaded or further processed.

Prerequisites/Requirements

• n8n Instance: A running instance of n8n.
• PostgreSQL Database: Access to a PostgreSQL database with the necessary connection details (host, port, database name, user, password).
• PostgreSQL Credentials: You will need to set up a PostgreSQL credential in your n8n instance.

Setup/Usage

1. Import the Workflow:
   • Copy the provided JSON code.
   • In your n8n instance, go to "Workflows" and click "New".
   • Click on the three dots menu (...) and select "Import from JSON".
   • Paste the JSON code and click "Import".
2. Configure PostgreSQL Node:
   • Locate the "Postgres" node (ID: 30).
   • Click on it to open its settings.
   • Under "Credentials", select your existing PostgreSQL credential or create a new one by clicking "Create New".
   • Configure the "Operation" (e.g., Read) and "Table" or "Query" to specify which data you want to retrieve. For example, you might use a SELECT * FROM your_table; query.
3. Configure Edit Fields (Set) Node (Optional):
   • Locate the "Edit Fields (Set)" node (ID: 38).
   • This node is currently a placeholder. You can configure it to:
     • Keep Only: Specify which fields from the PostgreSQL output you want to retain.
     • Remove: Specify fields to remove.
     • Rename: Rename fields.
     • Set: Add new fields or modify existing ones using expressions.
   • If no transformations are needed, you can leave it as is or remove it.
4. Configure Spreadsheet File Node:
   • Locate the "Spreadsheet File" node (ID: 41).
   • Ensure the "File Format" is set to your desired output (e.g., CSV).
   • You can also configure options like "Delimiter" for CSV files.
5. Execute the Workflow:
   • Click on the "When clicking ‘Execute workflow’" (Manual Trigger) node.
   • Click the "Execute Workflow" button in the top right corner of the n8n editor.
   • After execution, the "Spreadsheet File" node will output the generated file data, which you can then download from the node's output.