there is another index named, <str>, in this database

  Explanation:  The index name you tried to define already exists.
  This  message  is also printed during an IMPORT operation if the
  backup  file  contains  multiple  definitions   of   an   index.
  Duplicate  definitions may indicate corruption of the .RBR file,
  or improper operation during the EXPORT operation.

  User Action:  Try another index name.   If  this  message  arose
  during  an  IMPORT  operation,  then contact your Oracle support
  representative for assistance.