Paradigm mismatch is the problem when two different approaches are to be used at the same time. The most common case of this idiom is in between ObjectModeling and RelationalModeling.
ArgumentsThatTheObjectRelationalImpedanceMismatchDoesNotExist AvoidingImpedanceMismatch DatabaseImpedanceMismatch ImpedanceMismatch ObjectRelationalImpedanceMismatch ObjectRelationalImpedanceMismatchDoesNotExist ObjectRelationalImpedanceMismatchLinks RelationalHostLanguageImpedanceMismatch
Also related: MixingParadigms