You cannot use FastLoad, MultiLoad, or the Teradata Parallel Transporter operators LOAD and UPDATE to load data into base tables that have unique secondary indexes.
Before you can load data into a USI-indexed base table, you must first drop all defined USIs before you can run FastLoad, MultiLoad, or the Teradata Parallel Transporter operators LOAD and UPDATE.
Load utilities like Teradata Parallel Data Pump, BTEQ, and the Teradata Parallel Transporter operators INSERT and STREAM, which perform standard SQL row inserts and updates, are supported for USI-indexed tables.