Oracle error 904: ORA-00904: : invalid identifier

 Oracle error 904: ORA-00904: : invalid identifier

ORA-06512: at "SYSTEM.AD_DDL", line 2376

ORA-06512: at line 1 has been detected in afuddl() [6_xad].

do_array_ddl(APPLSYS, PA, 2, 1, 179, PA_EVENTS_DFV): private_do_array_ddl(APPS, APPLSYS, PA, 2, 1, 179, PA_EVENTS_DFV): do_array_c_view(1, APPS, PA_EVENTS_DFV, 1, 179): array_assign_and_execute(APPS, 1, 179, FALSE): : do_apps_array_ddl(APPS, 1, 179, FALSE): : substr($statement$,1,255)='CREATE OR REPLACE VIEW  PA_EVENTS_DFV 

 (ROW_ID, "CONTEXT_VALUE", PO_Number, PO_Line_Number, Employee, Quantity, Unit_Price, Item_Code, UOM, Attachment, 1111_TRANSACTION_NUM, PO_Line_Numb_,  

 CONCATENATED_SEGMENTS)  

 AS SELECT ROWID, ATTRIBUTE_CATEGORY,'

CREATE OR REPLACE VIEW PA_EVENTS_DFV 

 AS SELECT 'View generation has failed. Check log file for error messages' VIEW_HAS_FAILED_CHECK_LOG_FILE 

 FROM SYS.DUAL

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Start of log messages from FND_FILE

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End of log messages from FND_FILE

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No completion options were requested.

Output file size: 

866

Output is not being printed because:

The print option has been disabled for this report.

Solution:

Check the Column Names, Make sure Column name shouldn't start with Number or Special Characters