How to Link Work Orders Completion with Work Order in ODBC?

I am trying to get all of the work order completion transactions for a particular work order using the NetSuite data connector.

I can get the work order completion transactions with something like "select * from transaction where recordtype = 'workordercompletion';" and I can get the work order transactions with a similar query. What I can't find is anything that connects the two transaction types to each other.

I had a quick look at adding a custom field to the work order completion record. I thought I might be able to use the 'Created From' or 'Applied To Transaction' fields to link work orders to work order completions and then use that field in my SQL query. But there doesn't seem to be a way to add a field to the work order completion transaction.