ADSSTATS.SQL fails while applying R12.1.1 NLS Upgrade Patch 6678700

When attempting to Apply Patch 6678700,
the following error occurs.
ERROR
-----------------------
sqlplus -s APPS/***** AD_TOP\12.0.0\patch\115\sql\adsstats.sql 


Error:
Program exited with status 1

Cause: The program terminated, returning status code 1.

Action: Check your installation manual for the meaning of this code on this operating system.declare
*
ERROR at line 1:
ORA-20000: ORA-20001: invalid column name or duplicate columns/column
groups/expressions in method_opt Error while executing
FND_STATS.GATHER_SCHEMA_STATISTICS package.
ORA-06512: at line 91

ERROR: While running adsstats.sql :
object_name=FII.FII_FIN_ITEM_HIERARCHIES***ORA-20001: invalid column name or duplicate columns/column
groups/expressions in method_opt Error while executing
FND_STATS.GATHER_SCHEMA_STATISTICS package.
ORA-06512: at line 9

Solution

Please apply the following solution:
1. Make sure to have a valid backup for FND_HISTOGRAM_COLS table.

2. Run the following to delete column 'PARENT_FLEX_VALUE' from FND_HISTOGRAM_COLS.

delete from FND_HISTOGRAM_COLS
where table_name = 'FII_FIN_ITEM_HIERARCHIES'
and column_name = 'PARENT_FLEX_VALUE'

3- Restart the failed worker.