Step 2: Relations between tables

What this step is for

Tell the system how your tables join together (e.g. a loan_id column in collateral.csv matches id in loans.csv). Joins are what connect your separate tables into a single, complete asset tape — without them the system can't combine the data, so this step is required whenever you've uploaded more than one table.

When this step opens, the system has already analysed your tables and may suggest joins for you. Review those suggestions first, then add, edit or remove relations as needed.

How to do it

1. Review the list of uploaded files. Each card shows the file name, column count and row count.
2. Review any suggested joins the system has proposed. Confirm the ones that are correct and remove any that don't apply.
3. Click Add relation to open the Join dialog and define your own.
4. Choose:
   • Left table (e.g. loans)
   • Right table (e.g. collateral)
   • Column pair that links them (e.g. loans.id = collateral.loan_id)
5. Save the relation. Repeat for each pair of tables that needs to be joined.
6. Edit or delete a relation by clicking on it.
7. Click Next. The system runs a background Creating data mapping… job, which usually takes around a minute, before the Map columns step opens.

Tips

• Only add relations between tables that genuinely share keys. Spurious joins will multiply rows.
• If you only uploaded one file, you can skip straight to Next.