Solved

Oracle date time arithmetic: subtracting two dates to get minutes

Posted on 2012-03-27
4
776 Views
Last Modified: 2012-08-13
Hi there,

I need to subtract two datetime fields in Oracle to get the difference in minutes.
for example:
begin_lab_time = 2011.12.12 08:10:00
end_lab_time = 2011.12.12 08:31:00
expected result from subtracting these two fields: 21 minutes

How would I go about getting the expected result in Oracle?

I tried this but I get 20 minutes as the result and not 21 minutes. I need to get 21 minutes as the result:
trunc((86400*(end_lab_time-begin_lab_time))/60)-60*(trunc(((86400*(end_lab_time-begin_lab_time))/60)/60))
0
Comment
Question by:wdelaney05
  • 2
  • 2
4 Comments
 
LVL 73

Accepted Solution

by:
sdstuber earned 500 total points
ID: 37772326
(end_lab_time - begin_lab_time) * 1440
0
 

Author Comment

by:wdelaney05
ID: 37772436
ah. getting closer. I get 20.99999999999999999999999999999999999995 as the result, sdstuber. Is it best to use ROUND, then to get 21?
0
 
LVL 73

Expert Comment

by:sdstuber
ID: 37772485
interesting.... I get different results based on whether I'm executing within pl/sql context or not.

SQL> SELECT (end_lab_time - begin_lab_time) * 1440
  2    FROM (SELECT TO_DATE('2011.12.12 08:10:00', 'yyyy.mm.dd hh24:mi:ss') begin_lab_time,
  3                 TO_DATE('2011.12.12 08:31:00', 'yyyy.mm.dd hh24:mi:ss') end_lab_time
  4            FROM DUAL);

(END_LAB_TIME-BEGIN_LAB_TIME)*1440
----------------------------------
                                21

SQL> DECLARE
  2      v_result         NUMBER;
  3      begin_lab_time   DATE := TO_DATE('2011.12.12 08:10:00', 'yyyy.mm.dd hh24:mi:ss');
  4      end_lab_time     DATE := TO_DATE('2011.12.12 08:31:00', 'yyyy.mm.dd hh24:mi:ss');
  5  BEGIN
  6      v_result  := (end_lab_time - begin_lab_time) * 1440;
  7      DBMS_OUTPUT.put_line(v_result);
  8
  9      SELECT (end_lab_time - begin_lab_time) * 1440 INTO v_result FROM DUAL;
 10
 11      DBMS_OUTPUT.put_line(v_result);
 12
 13      DBMS_OUTPUT.put_line((end_lab_time - begin_lab_time) * 1440);
 14  END;
 15  /
20.99999999999999999999999999999999999995
20.99999999999999999999999999999999999995
20.99999999999999999999999999999999999995

PL/SQL procedure successfully completed.

Open in new window



So, I guess...
yes, if you want to do your date math in pl/sql then you'll have to round it to get your results.
0
 

Author Comment

by:wdelaney05
ID: 37772507
Re: So, I guess...
yes, if you want to do your date math in pl/sql then you'll have to round it to get your results.

ok, for my purposes, I will use ROUND; that works for my results.
Thanks very much for your help, it's much appreciated!
0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
Need help with Oracle syntax 4 56
Pfile and SPfile - Oracle 2 57
How to count the number of rows in multiple Oracle Tables 10 63
Fastest way to replace data in Oracle 5 51
Working with Network Access Control Lists in Oracle 11g (part 1) Part 2: http://www.e-e.com/A_9074.html So, you upgraded to a shiny new 11g database and all of a sudden every program that used UTL_MAIL, UTL_SMTP, UTL_TCP, UTL_HTTP or any oth…
This post first appeared at Oracleinaction  (http://oracleinaction.com/undo-and-redo-in-oracle/)by Anju Garg (Myself). I  will demonstrate that undo for DML’s is stored both in undo tablespace and online redo logs. Then, we will analyze the reaso…
This video explains at a high level about the four available data types in Oracle and how dates can be manipulated by the user to get data into and out of the database.
This video shows syntax for various backup options while discussing how the different basic backup types work.  It explains how to take full backups, incremental level 0 backups, incremental level 1 backups in both differential and cumulative mode a…

920 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

12 Experts available now in Live!

Get 1:1 Help Now