Oracle uses the original start date of the Gregorian calendar in October
1582:
 
  1* select to_date('04-OCT-1582'), to_date('04-OCT-1582')+1 from dual
devp> /
 
TO_DATE('04-OCT-1582 TO_DATE('04-OCT-1582
-------------------- --------------------
04-OCT-1582 00:00:00 15-OCT-1582 00:00:00
Ben Schilling
Telecomm Manager
Office of the Commissioner of Insurance
608-266-1615 [EMAIL PROTECTED] 

-----Original Message-----
Sent: Wednesday, December 19, 2001 11:09 AM
To: Multiple recipients of list ORACLE-L


Well I say,
 
that is also the case on Tru64 as well.
 
How pedantic is UNIX ??
 



-----Original Message-----
Sent: 19 December 2001 16:16
To: Multiple recipients of list ORACLE-L


Speaking of the system clock, here's something interesting that I stumbled
across a few years back... 

Background:  For those of you who may not know, the Julian calendar was
abandoned by England, in favor of the Gregorian calendar, in 1752 because of
date discrepancies.  To facilitate this, September 3 - 13 were eliminated.
This is actually reflected in UNIX (well, Solaris anyway) by issuing the
'cal 1752' command and looking at the month of September: 


        Jul                    Aug                    Sep 
 S  M Tu  W Th  F  S    S  M Tu  W Th  F  S    S  M Tu  W Th  F  S 
          1  2  3  4                      1          1  2 14 15 16 
 5  6  7  8  9 10 11    2  3  4  5  6  7  8   17 18 19 20 21 22 23 
12 13 14 15 16 17 18    9 10 11 12 13 14 15   24 25 26 27 28 29 30 
19 20 21 22 23 24 25   16 17 18 19 20 21 22 
26 27 28 29 30 31      23 24 25 26 27 28 29 


More info. on why the switch over occurred is available at
http://www.bicknell.net/books/pc1981/p_calender.htm
<http://www.bicknell.net/books/pc1981/p_calender.htm> , for those of you
with morbid curiosity. 


Anyway - I was doing some Y2K testing a few years back, and playing with
NLS_DATE_FORMAT queries when I learned this little tidbit.  I decided to
test the Oracle date formats because - hey - they'll be okay because they're
based on Unix, right? 


Wrong:  Issue the following query: 


select     sysdate 
            ,add_months(sysdate,-2988) 
            ,add_months(sysdate,-2988) - 10 
from dual; 


And see the following results: 


SYSDATE              ADD_MONTHS(SYSDATE,- ADD_MONTHS(SYSDATE,- 
-------------------- -------------------- -------------------- 
19-DEC-2001 10:07:02 19-DEC-1752 10:07:02 09-DEC-1752 10:07:02 


The third column represents a date which, technically, does not exist.  : ) 


Brian 


Kimberly Smith wrote: 


Oracle uses the system clock.  So I would have to say no. 

-----Original Message----- 
Pollard 
Sent: Tuesday, December 18, 2001 6:50 PM 
To: Multiple recipients of list ORACLE-L 


Gooday Oraclers, 
is it possible to have different instances, on the same dB server, 
operating with different clocks - ie different date/times? 


Environment: Compaq-Digital Tru64 Unix, Oracle 8.0.6, DS20 


--- 
               Kevin Pollard  |  PODBA (Pretend Oracle DBA) 
  mailto:[EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]>   |
Administrative Systems Unit 
    Phone:+61 (02) 6620 3969  |  Southern Cross University 
      FAX:+61 (02) 6626 9122  |  P.O. Box 157 
                Room: R1-40a  |  Lismore NSW 2480, Australia 
          http://staff.scu.edu.au/asu/index.html
<http://staff.scu.edu.au/asu/index.html>  


-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.com
<http://www.orafaq.com>  
-- 
Author: Kevin Pollard 
  INET: [EMAIL PROTECTED] 


Fat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051 
San Diego, California        -- Public Internet access / Mailing Lists 
-------------------------------------------------------------------- 
To REMOVE yourself from this mailing list, send an E-Mail message 
to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in 
the message BODY, include a line containing: UNSUB ORACLE-L 
(or the name of mailing list you want to be removed from).  You may 
also send the HELP command for other information (like subscribing). 
-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.com
<http://www.orafaq.com>  
-- 
Author: Kimberly Smith 
  INET: [EMAIL PROTECTED] 


Fat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051 
San Diego, California        -- Public Internet access / Mailing Lists 
-------------------------------------------------------------------- 
To REMOVE yourself from this mailing list, send an E-Mail message 
to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in 
the message BODY, include a line containing: UNSUB ORACLE-L 
(or the name of mailing list you want to be removed from).  You may 
also send the HELP command for other information (like subscribing).

-- 
-------------------------------------- 
| Brian McGraw     --     Oracle DBA | 
| Central Alabama Oracle Users Group | 
|------------------------------------| 
| mailto:[EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]>       | 
| http://bmcgraw.home.mindspring.com <http://bmcgraw.home.mindspring.com>  |

-------------------------------------- 
  



The information contained in this communication is
confidential, is intended only for the use of the recipient
named above, and may be legally privileged. If the reader 
of this message is not the intended recipient, you are
hereby notified that any dissemination, distribution or
copying of this communication is strictly prohibited. 
If you have received this communication in error, please 
re-send this communication to the sender and delete the 
original message or any copy of it from your computer
system.


-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.com
-- 
Author: Schilling, Ben
  INET: [EMAIL PROTECTED]

Fat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051
San Diego, California        -- Public Internet access / Mailing Lists
--------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).

Reply via email to