Getting error while upgrading report from 8.1 to 8.3

[dipstm]

Hi All,
I have one report which used to run fine on Cognos 8.1 but after upgrading it to Cognos 8.3 it shows the below errors :

QE-DEF-0459 CCLException
RQP-DEF-0177 An error occurred while performing operation 'sqlPrepareWithOptions' status='-459'.
UDA-SQL-0459 Ambiguous column reference is usually caused by trying to select unnamed columns or when there are duplicate column names

I am not able to understand what seems to be the problem.
Can anyone plz let me know wat is cause for this?
Thanx in advance