Copy lists with circular lookups

This article will take you through an example of how to copy lists with circular lookups.

For the example, assume you have List A and List B with a circular lookup between them, where List A points to List B, and List B points back to List A.

Part 1

1. In your source List A, set the lookup columns to Not required in the column settings.
2. In the ShareGate migration tool, select the Copy structure and content option from the Copy menu. Then connect to your source and destination sites.
3. In the navigation pane on the left, click on List and libraries and select List A.
4. Click Options on the top-right.
5. Under Configurations, un-check List content. Save and close the options. 
6. Click Start copy.

When the migration is complete, you should have an empty list at your destination.

Part 2

1. Return to the Copy menu in the ShareGate app.
2. Select Copy content only. Connect to the original List A as the source, and the newly created List A as the destination.
3. Click Mappings on the top-right. 
4. Select the Properties tab.
5. Under Source, hover your mouse over the column that contains the lookup column and click the (X) that appears.
6. Click Save. This will allow the app to skip the column since it is not required.
7. Select all items in the left pane.
8. Click Start copy.

When the migration is complete, you should have the list at the destination, and only the data from the lookup columns will be missing.

Part 3

1. Migrate List B using the Copy structure and content option in the Copy menu.
2. Select Copy content only, and connect to List A as the source and destination. Copy the property values you removed in step (5) of Part 2 back into List A, and close this window.
3. Once that's done, migrate List A again using the Copy structure and content option in the Copy menu.

You should now have a list at the destination with all the required column information for the lookup to get populated.