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:
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Warehouse A: Our main, "source of truth" database. This is the master list of what our inventory should be.
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Warehouse B: A second, remote database (like a Notion page or Google Sheet) that we need to keep in sync.
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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:
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In A only: New products found in our main warehouse that need to be added to Warehouse B.
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Same: Products that match perfectly in both warehouses. No action needed!
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Different: Products that exist in both places but have different details (eg, stock count). These need to be updated in Warehouse B.
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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.
Setup steps
Setup time: 0 minutes!
This workflow is a self-contained tutorial and requires no setup or credentials.
- Click "Execute Workflow" to start the audit.
- Explore the two
Set nodes ("Warehouse A" and "Warehouse B") to see the initial data we are comparing.
- Click on "The Auditor" (Compare Datasets node) to see how it's configured to use
product_id as the matching key.
- Follow the outputs to the four
NoOp nodes to see which products were sorted into each category.
- Read the sticky notes next to each output—they explain exactly why each item ended up there.
