Hi Vimesh,
The RDM Utiilities collection currently does not have specific functionality for unmapped lookup values.
However, if you are referring to the fact that the Lookup API that has a limit of 100 to post or 1000 to get... the recipes for clone/remove, get/post, rdm dataloader - all have looping in the logic to post 100 at a time and loop as many times as needed to get them all posted automatically.
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Michelle Popovits
Technical Consultant
Reltio
ON
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