Conversion from date to number & display a date in a textfield

Question

I Have 2 issues
The first one:
I need to extract the hour from a date variable.
This is the code I already have:
NUM_TOT := NUM_TEL + to_number('PROGRAMMINGS1.PRG_START','hh24');
NUM_TOT & NUM_TEL are number variables,
PROGRAMMINGS1.PRG_START is a Textfiel with a dateformat. There can only be an houre like 24:59:00 entered.
So in this example I just want the houre and convert it to a number.
The second:
I want to make a date from a few numbers & then display it in a texfield.
This is the code I already have:
VAR_DATE := NUM_TEL || ':' || NUM_LENGTH || ':00';
:PROGRAMMINGS.PRG_END := to_date(VAR_DATE,'hh24:mi:ss');
Between the 2 lines of code i places a message(VAR_DATE) for testing.
When the program display VAR_DATE then i can see the good date at the bottom of the screen.
But when I place my variable in the textfield it looks like: 00:00:00. What am I doing wrong?
Who can help me.
With regards
Stefanie

Answer 1

Verdi wrote:
Problem: During the conversion (both implicit and explicit conversion with a format mask) I lose the "00" hours and "00" minutes and receive something like this: "10-JAN-13 *12*.00.00.000000000 AM".I don't think you are necessarily losing any information whatsoever. It's probably more of a function of your NLS_TIMESTAMP_FORMAT and NLS_DATE_FORMAT. For example your NLS_DATE_FORMAT could be setup by default for a HH24 (24 hour time) which would report midnight as "00" hours. However, it looks like your NLS_TIMESTAMP_FORMAT is setup with a "HH" format with a meridian indicator which means 12 hours time.
Your comparisons should be using date/timestamp data types anyways so as long as the input value is converted properly into a date type this shouldn't matter anyways.
You can see what is actually stored by using the DUMP function:
SQL> SELECT  DUMP(TO_TIMESTAMP(TO_CHAR(TRUNC(SYSDATE,'DD'),'MM/DD/YYYY HH:MI:SS AM'))) AS TSTAMP
  2  ,       DUMP(TRUNC(SYSDATE,'DD')) AS DT
  3  FROM DUAL
  4  /
TSTAMP                                                                      DT
Typ=187 Len=20: 218,7,1,13,0,0,0,0,0,0,0,0,0,0,3,0,0,0,0,0                  Typ=13 Len=8: 218,7,1,13,0,0,0,0As you can see the TSTAMP and DT store nearly the same values (218,7,1,13), but the TSTAMP has more precision because of fractional seconds.
HTH!
Edited by: Centinul on Jan 13, 2010 7:23 AM