Learn Data Synchronization: Warehouse Inventory Audit Tutorial

## How it works This template is a hands-on tutorial for one of n8n's most powerful data tools: the **Compare Datasets** node. It's the perfect next step after learning basic logic, showing you how to build robust data synchronization workflows. We use a simple **Warehouse Audit** analogy to make the concept crystal clear: * **Warehouse A:** Our main, source of truth database. This is the master list of what our inventory should be. * **Warehouse B:** A second, remote database (like a Notion page or Google Sheet) that we need to keep in sync. * **The Compare Datasets Node:** This is our **Auditor**. It takes both inventory lists and meticulously compares them to find any discrepancies. The Auditor then sorts every item into one of four categories, which correspond to the node's four outputs: 1. **In A only:** New products found in our main warehouse that need to be **added** to Warehouse B. 2. **Same:** Products that match perfectly in both warehouses. **No action needed!** 3. **Different:** Products that exist in both places but have different details (e.g., stock count). These need to be **updated** in Warehouse B. 4. **In B only:** Extra products found in Warehouse B that aren't in our master list. These need to be **deleted**. This pattern is the foundation for any two-way data sync you'll ever need to build. ## Set up steps **Setup time: 0 minutes!** This workflow is a self-contained tutorial and requires no setup or credentials. 1. Click **Execute Workflow** to start the audit. 2. Explore the two `Set` nodes (Warehouse A and Warehouse B) to see the initial data we are comparing. 3. Click on **The Auditor (Compare Datasets node)** to see how it's configured to use `product_id` as the matching key. 4. Follow the outputs to the four `NoOp` nodes to see which products were sorted into each category. 5. Read the sticky notes next to each output—they explain exactly why each item ended up there.