Scenario 11: ORA-01502: index 'XYZ.UNIQUE_UK1' or partition of such index is in unusable state

Answer: This is error which is Related to Database table XYZ having Unique index UNIQUE_UK1. the Index was Dropped by somehow, so due to this we are getting this error.

Resolution: we have to Ask the DBA Guys to Recreate the indexes or we need to build the index manually. once indexes are built, we are good to restart the job.

***Note***

Generally indexes will be dropped if there are any Duplicate Records in the table.