# PostgreSQL

The **PostgreSQL Node** allows you to query a PostgreSQL database directly from your workflow. It is designed to take a user’s question (in plain English or SQL), convert it into a SQL query if needed, execute it against your connected PostgreSQL database, and return the results.

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#### Required Inputs

1. **Query** (string, required)
   * This is the main input. You can enter your question in plain English (e.g., "Show me the top 10 customers by revenue") or provide a raw SQL query.
   * The node will interpret the plain English query and generate the appropriate SQL, or execute your SQL directly.
2. **Schema** (array of strings, optional but recommended)
   * This is where you can provide the database schema (tables, columns, types, etc.) to help the node understand your database structure.
   * Example:

     ```
     TABLE Customers (Name TEXT, Email TEXT, Revenue REAL);
     TABLE Orders (OrderID INT, CustomerID INT, Amount REAL);
     ```
   * Providing the schema is especially helpful if you want the node to convert plain English to SQL accurately.

#### Output

* **Query**: The actual SQL query that was executed.
* **Results**: The results of the query, returned as an array of objects (rows).

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### Example Usage

* **Plain English Query:**\
  Input: "What is the total revenue for the year 2024?"\
  Output: The node will generate the SQL, run it, and return the result.
* **SQL Query:**\
  Input: `SELECT SUM(revenue) FROM sales WHERE year = 2024;`\
  Output: The node will execute this SQL and return the result.

***

### How to Connect

* If you have a PostgreSQL connection ID, you can add it to the node’s configuration to connect to your specific database.
* You can connect the output of this node to downstream nodes (like an LLM for analysis, or an Output node for display).

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### Summary Table

| Input Name  | Type   | Required | Description                                    |
| ----------- | ------ | -------- | ---------------------------------------------- |
| query       | string | Yes      | The question or SQL to execute                 |
| sql\_schema | array  | No       | Database schema (tables, columns, types, etc.) |

| Output Name | Type   | Description                     |
| ----------- | ------ | ------------------------------- |
| query       | string | The SQL query that was executed |
| results     | array  | The results of the query        |

***

If you want to use this node, just provide your question or SQL, and (optionally) the schema. The node will handle the rest—querying your PostgreSQL database and returning the results for use elsewhere in your workflow!


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# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.stackai.com/workflow-builder/apps/postgresql.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.