How to get the date-time value?

Question

Hi All
I have a a field "START_TIME of type DATE". The value stored for that particular field is of the form "10/17/2006 2:23:40 PM" i.e. a date-time value.
Now when i try to get the values stored in the table in which the START_TIME field is defined i get the value in the form of "10/17/2006" .... I missed out the time information. Why is this so? How do i get the complete value as a string?
Thanks in advance. Vijay

Answer 1

Hi All
I have a a field "START_TIME of type DATE". The value stored for that particular
field is of the form "10/17/2006 2:23:40 PM" i.e. a date-time value.Actually it is stored as an internal date format (see my example SQL below, taking note of the dump'ed data).
Now when i try to get the values stored in the table in which the START_TIME field is defined i get the
value in the form of "10/17/2006" ....
I missed out the time information. Why is this so?
How do i get the complete value as a string?The value you see on the screen is the display format and this is determined by the client application that is displaying the date and what settings it is using. If a date column is retrieved from the database then all the data (date and time) is given back, but it's up to the application how that is displayed. e.g. you may see it differently if you view it is SQL*Plus against some other tool such as TOAD.
To change the display settings you can change your NLS_DATE_FORMAT setting or whatever setting is suitable for your client application, or you can use TO_CHAR with a format string to specify the components you want to see. The different with TO_CHAR is that you are converting it to a character string so don't attempt to do any date type comparisons on it after that conversion, e.g. don't try and compare if one date is greater than another, without converting it back to DATE datatype first.
SQL> create table t (x date);
Table created.
SQL> insert into t (x) values (sysdate);
1 row created.
SQL> select x from t;
X
02-JUN-08
SQL> select x, dump(x) from t;
X
DUMP(X)
02-JUN-08
Typ=12 Len=7: 120,108,6,2,13,32,51
SQL> alter session set nls_date_format = 'DD/MM/YYYY HH24:MI:SS';
Session altered.
SQL> select x, dump(x) from t;
X
DUMP(X)
02/06/2008 12:31:50
Typ=12 Len=7: 120,108,6,2,13,32,51
SQL>