Yes, adding a join_type clause fixed the problem.

I had seen the documentation you referred to I but had misinterpreted it to mean that NULL optional foreign key fields would just work out of the box and that the left join clauses might be needed in the context of obtaining rows of cars rather than also to moderate side-effects (not knocking what is going on behind the scenes - it's great, just that I don't understand it all).

Thank you

In reply to Re^2: DBIx, using belongs_to on optional field, insert-by-side-effect in foreign table by smallvaluesof2
in thread DBIx, using belongs_to on optional field, insert-by-side-effect in foreign table by smallvaluesof2

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