I think in your case max(ActionDate) not equal max(Sequence). Use either one of them, I believe you want max (Sequence), not max(Date).
See changes inside.
>>>select LH.* from LocationHistory LH inner join (select Max(Sequence) as Seq,
>>> PartID, SerialNo from LocationHistory group by PartID, SerialNo ) Derived on
>>> LH.Sequence = Derived.Seq and LH.PartID = Derived.PartID and LH.SerialNo = Derived.SerialNo
>
>This is almost there, except I get back rows 2292, 2924, and 2923.
>
>
If it's not broken, fix it until it is.
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