Hi Vijaya,
instead of comparing the values, use the 'equals' or 'not equals' comparator which lets you test for a particular value. So if you are using an AND condition 'DO_NOT_MERGE' EQUALS false then it will be a merge candidate. You are probably better off making it a negative compare to account for times the attribute is not populated.
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Gino Fortunato
Principal Solution Engineer
Reltio
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