ORA-01830 - date format picture ends... - but only in where clause - not in select

Question

I created an easier to test post here: ORA-01847 day of month must be between 1 and last day of month - but data is OK Problem solution described there

It took me hours to search for a comparable issue in the web - finally i think only you out there can help me.

I send my Query to Oracle 11 via SQL developer.

You may ignore the complete subselect (its in pastebin) - i added a dump of each column to see details.

I got big Problems when comparing timestamps in where clause: here my basic sql without where clause in last line:

select prod,operating,fakeday,prod_origin,operating_origin,
dump(prod),dump(fakeday),dump(operating) from 
(
http://pastebin.com/wqX7dJPA
) sub
-- works: where sub.operating < to_timestamp('20140101','YYYYMMDD')
-- works: where sub.fakeday < to_timestamp('20140101','YYYYMMDD')
-- works NOT: where sub.prod < to_timestamp('20140101','YYYYMMDD')

Result without where clause is:

    'PROD'|                    'OPERATING'|                'FAKEDAY'|                  'PROD_ORIGIN'|'OPERATING_ORIGIN'|'DUMP(PROD)'|                                          'DUMP(FAKEDAY)'|                                              'DUMP(OPERATING)'
    25.11.13 00:00:00,000000000|25.11.13 00:00:00,000000000|25.11.13 00:00:00,000000000|',20131125,'|'25.11.2013'|      'Typ=187 Len=20: 7,221,11,25,0,0,0,0,0,0,0,0,0,0,3,0,0,0,0,0'|'Typ=187 Len=20: 7,221,11,25,0,0,0,0,0,0,0,0,0,0,3,0,0,0,0,0'|'Typ=187 Len=20: 7,221,11,25,0,0,0,0,0,0,0,0,0,0,3,0,0,0,0,0'
    24.02.14 00:00:00,000000000|24.02.14 00:00:00,000000000|24.02.14 00:00:00,000000000|',20140224,'|'24.02.2014'|      'Typ=187 Len=20: 7,222,2,24,0,0,0,0,0,0,0,0,0,0,3,0,0,0,0,0'|'Typ=187 Len=20: 7,222,2,24,0,0,0,0,0,0,0,0,0,0,3,0,0,0,0,0'|'Typ=187 Len=20: 7,222,2,24,0,0,0,0,0,0,0,0,0,0,3,0,0,0,0,0'
    28.10.13 00:00:00,000000000|28.10.13 00:00:00,000000000|28.10.13 00:00:00,000000000|',20131028,'|'28.10.2013'|      'Typ=187 Len=20: 7,221,10,28,0,0,0,0,0,0,0,0,0,0,3,0,0,0,0,0'|'Typ=187 Len=20: 7,221,10,28,0,0,0,0,0,0,0,0,0,0,3,0,0,0,0,0'|'Typ=187 Len=20: 7,221,10,28,0,0,0,0,0,0,0,0,0,0,3,0,0,0,0,0'
    28.10.13 00:00:00,000000000|28.10.13 00:00:00,000000000|28.10.13 00:00:00,000000000|',20131028,'|'28.10.2013'|      'Typ=187 Len=20: 7,221,10,28,0,0,0,0,0,0,0,0,0,0,3,0,0,0,0,0'|'Typ=187 Len=20: 7,221,10,28,0,0,0,0,0,0,0,0,0,0,3,0,0,0,0,0'|'Typ=187 Len=20: 7,221,10,28,0,0,0,0,0,0,0,0,0,0,3,0,0,0,0,0'
    20.01.14 00:00:00,000000000|20.01.14 00:00:00,000000000|20.01.14 00:00:00,000000000|',20140120,'|'20.01.2014'|      'Typ=187 Len=20: 7,222,1,20,0,0,0,0,0,0,0,0,0,0,3,0,0,0,0,0'|'Typ=187 Len=20: 7,222,1,20,0,0,0,0,0,0,0,0,0,0,3,0,0,0,0,0'|'Typ=187 Len=20: 7,222,1,20,0,0,0,0,0,0,0,0,0,0,3,0,0,0,0,0'

If i add the where clause in last line filtering on 'prod' i'll run into

ORA-01830: Datumsformatstruktur endet vor Umwandlung der gesamten Eingabezeichenfolge
01830. 00000 -  "date format picture ends before converting entire input string"
*Cause:    
*Action:

If i'm using the other column sub.operating or sub.fakeday i'll receive correct filtered resultlist.

where sub.operating < to_timestamp('20140101','YYYYMMDD')

another important information - i can call

select prod,operating,prod-operating,fakeday

and it will work -> shows a interval result for prod-operating

BUT

where prod - operating = INTERVAL '0' DAY;

will lead to:

 ORA-01847: Tag des Monats muss zwischen 1 und letztem Tag des Monats liegen
 01847. 00000 -  "day of month must be between 1 and last day of month"

Please help - i don't have any idea.

Answer 1

alter session set nls_date_format = 'DD.MM.YYYY HH24:MI:SS';