How to convert the date format 'm/d/yyyy hh:mi:ss AM' to 'MM/DD/YYYY HH:M'

Question

How can i convert a the date format 'm/d/yyyy hh:mi:ss AM' to 'MM/DD/YYYY HH:MI:SS AM' in Oracle
I have a query
select UPPER(t.val_10) "TYPE", count(val_3) "Number of Transfers"
from table1 t
where t.is_active = 1
and t.val_4 = 'INBOUND'
and to_date(to_date(val_5,'MM/DD/YYYY HH:MI:SS AM'), 'DD/MM/YY') between to_date(to_date('01/08/2008 00:00:00','DD/MM/YYYY HH24:MI:SS'), 'DD/MM/YY') and add_months(to_date(to_date('01/08/2008 00:00:00','DD/MM/YYYY HH24:MI:SS'), 'DD/MM/YY'),1)
group by UPPER(t.val_10)
order by UPPER(t.val_10)
I get the error [ORA-01861: literal does not match format string which i think is because
val_5 has the values in the following format:
8/29/2008 6:31:10 PM
Does anyone have an answer?
Thanks in advance
Edited by: user2360027 on 26-Mar-2009 03:50                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               

Answer 1

first off, you've got to_date(to_date(...)) - NEVER do this - you're forcing an implicit to_char which can cause all sorts of problems!
What is the data type of your column val_5? If it's DATE then your query is simply:
select UPPER(t.val_10) "TYPE",
       count(val_3) "Number of Transfers"
from   table1 t
where  t.is_active = 1
and    t.val_4 = 'INBOUND'
and    val_5 between to_date('01/08/2008','DD/MM/YYYY') and add_months(to_date('01/08/2008','DD/MM/YYYY') ,1)
group by UPPER(t.val_10)
order by UPPER(t.val_10)If it's a varchar2 (why, oh why, oh why, ...?!), then your query should be:
select UPPER(t.val_10) "TYPE",
       count(val_3) "Number of Transfers"
from   table1 t
where  t.is_active = 1
and    t.val_4 = 'INBOUND'
and    to_date(val_5, 'mm/dd/yyyy hh:mi:ss AM') between to_date('01/08/2008','DD/MM/YYYY') and add_months(to_date('01/08/2008','DD/MM/YYYY') ,1)
group by UPPER(t.val_10)
order by UPPER(t.val_10)Remember that dates in DATE format are stored in an internal Oracle format - in order for you to tell Oracle that your string is a date, you need to use to_date. When you want to retrieve a date, you need to use to_char to put it into the format you want to see it in.
Remember also that your nls_date_format defines the default format that you'll see a date, which is what is used in the implicit conversion that oracle does when you select a date:
SQL> alter session set nls_date_format='dd/mm/yyyy hh24:mi:ss';
Session altered.
SQL> select sysdate from dual;
SYSDATE
26/03/2009 11:01:53
1 row selected.
SQL> alter session set nls_date_format='mm/dd/yy hh12:mi:ss AM';
Session altered.
SQL> select sysdate from dual;
SYSDATE
03/26/09 11:02:24 AM
1 row selected.It doesn't make sense to convert something that's already in a DATE format into a DATE format - in order to do that, oracle has to first change the date into a string, and it does that by using the nls_date_format parameter setting - if you're working with dates-in-strings that are in a different format, then all sorts of problems arise, as you have found out!