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If you choose Add, concepts will be included into an already existing TermBase. No terms will be deleted, overwritten or modified. You cannot keep concept IDs from source in this caseThe original concept ID will alsways be kept when using Add.
Replace concepts
If you choose Replace, the entire TermBase will be purged before import proceeds. You may choose to keep the concept IDs from source in this case by clicking the checkbox Import concept ID from source.
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