DataJoiner Help Center

1. Define Your Sheets

Source Sheet (Main Data): The rows you want to enrich.

Lookup Sheet (Data to Join): The information you want to fetch.

Target Sheet: Where the results go. Often the same as your Source Sheet.

2. Select Key Columns

Key Columns must contain matching values between sheets — like SKUs, IDs, or emails.

Source Key Column: From your Source Sheet.
Lookup Key Column: From your Lookup Sheet.

3. Create Column Mappings

This controls which columns you copy over and where they go.

Column to Return: The column in the Lookup Sheet to fetch.
Target Column: Where it will be placed.

You can add multiple mappings at once.

4. Create the Join

Click Run Operation. DataJoiner will generate formulas, process them, and paste final results into your Target Sheet.

💡 Best Practices

Make sure your Lookup Key Column has unique values. If duplicates exist, the operation will always return the first match found.

Troubleshooting Results

Problem: Blank results
Cause: Key values do not match exactly.
Fix: Look for extra spaces or inconsistent formatting.

Problem: Wrong value returned
Cause: Duplicate keys in Lookup Sheet.
Fix: Ensure the first occurrence is the one you want.

Problem: “Return column cannot be left of lookup key”
Cause: VLOOKUP limitation.
Fix: The return column must be to the right of the key column.

"Select a file" doesn't load?

Cause: Browser privacy settings (Firefox or Chrome Incognito) may block the Google login popup.

Fix:

Firefox: Click the Shield icon 🛡️ next to the URL bar and turn OFF "Enhanced Tracking Protection".
Chrome: Ensure "Block third-party cookies" is disabled if using Incognito.