Hey Mark,
Great tip, but I am having an issue with the Bulk Upsert..I will want it to Trigger when someone creates an Invoice record so I set it up like this and everything works, but when it upserts back into the Time Entry table it doesn't update the Related Invoice field with the Invoice number that was just created in the Invoice Table. I am sure this is a total operator error on my end...first bulk upsert. Thank you for helping!
A - Record Created - 
       Table - Invoices
       Fields Used - Related Prospect, Period From Date, Period To Date
B - Prepare Bulk Record Upsert
      Table - Time Entries
      Fields - Related Invoice
      Merge Field Record ID
C - Search Records
      Table - Time Entries
      Fields - Related Invoice, Related Prospect, Date
      Query - Related Prospect = a.related_prospect & Date is Between a.periodfrom - a.periodto
For Each Record
     Do
     D - Add a Bulk Upsert Row 
     Bulk Record set = B Bulk Record Set
     Related Invoice = c.related_invoice
     Record ID# = c.id
E. Commit Upsert
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Ryan Locke
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