Date Format in 'HH:MI' - help needed

Question

I have a table details that contains time_status column of Timestamp datatype.
Data is stored in the column in the format '1/1/2008 10:31:00.000000 AM'.
Now I want to select the data in HH:MI fopmat only.
i.e., for '1/1/2008 10:31:00.000000 AM' I should get 10:31.
I have written as select to_char(time_status,'HH:MI') from dual;
I am getting an error when this query is included in the procedure.
When I am executing outside, its is working.
Also, How can I get the format a '1/1/2008 10:31'.
Thanks in advance.
Regards
Raghunadh.

Answer 1

I have a table details that contains time_status column of Timestamp datatype.Good. Always use the correct datatype. Either date or timestamp.
Data is stored in the column in the format '1/1/2008 10:31:00.000000 AM'.
Wrong! A timestamp or also a date column has no format! Same as a number column has no format.
Now I want to select the data in HH:MI fopmat only. i.e., for '1/1/2008 10:31:00.000000 AM' I should get 10:31.When you work with date and timestamps you don't need any format. When you display the value, then you need to change your date into a string. Only during this transformation formatting takes place.
Example:
SQL*Plus: Release 9.2.0.2.0 - Production on Thu Aug 21 10:45:17 2008
Copyright (c) 1982, 2002, Oracle Corporation.  All rights reserved.
Connected to:
Oracle9i Enterprise Edition Release 9.2.0.8.0 - 64bit Production
With the Partitioning, OLAP and Oracle Data Mining options
JServer Release 9.2.0.8.0 - Production
/* lets do a simple date select */
SQL> select sysdate from dual;
SYSDATE
21-AUG-08
"Attention!" Sql*Plus did an implizit date to string conversion to show this value on the screen.
It used the NLS settings for the format.
/* Now lets change the nls settings */
SQL> alter session set nls_date_format = 'FMddth Month YYYY';
Session altered.
SQL> select sysdate from dual;
SYSDATE
21st August 2008
SQL>
"Different output for the same query! Value is the same, only the formatting was changed."
I have written as select to_char(time_status,'HH:MI') from dual;You should ask yourself, why do I want this string?
I am getting an error when this query is included in the procedure.
When I am executing outside, its is working.
Also, How can I get the format a '1/1/2008 10:31'.Check the documentation (sql manual) for the many options for the date format settings. Also check for timestamps, they are a bit more difficult to handle than dates.
Thanks in advance.
Regards
Raghunadh.You're welcome.