You will need to set the Key field to be the result of a formula which concatenates the Related Project and the Date. There would need to be a formula calculation and then a form rule to populate the new key field with the value of he formula or else some kind of Automaton to auto create forcasts records with the correct Key.
Then the child table will be able to calculate the same Key by formula so it will Link up to he correct Forecast. But in your response you said that there was not a direct relationships between Visits and Projects. The problem will be that a lookup field may not be used in a formula for the reference field on he right side of a relationship if it involves a lookup field.
The only work around to THAT is to have an automation backup up I suggest by a an overnight saved table to table import running via an Automation to copy over the lookup field into the scaler (data input) field.
So the formula would be like
List("-" ToText([Related Project Maintained by Automation], ToText([visit date])))
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Mark Shnier (YQC)
Quick Base Solution Provider
Your Quick Base Coach
http://QuickBaseCoach.commark.shnier@gmail.com
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