Laurent Schneider

select add_months(date '1990-02-28',18*12) from dual;
ADD_MONTHS(DATE'199
-------------------
29.02.2008 00:00:00

Put your code in <code> and </code> tags

9 Responses to “Are you really 18 years old today?”

1. Claudia Zeiler Says:
   February 28th, 2008 at 19:11

   Hi Laurent,
   The person born Feb 29, 1992 acquires the day the the one born Feb 28, 1990 lost.

   1* select add_months(date ‘1992-02-29′,18*12) from dual
   SQL> /

   ADD_MONTH
   ———
   28-FEB-10

   By the way, do you know “The Pirates of Penzance”? The whole plot turns around the hero who was indentured to pirates until his 21st birthday. BUT he was born Feb 29. No one ever claimed that Gilbert and Sullivan make sense. )
   -Claudia

2. Laurent Schneider Says:
   February 28th, 2008 at 19:19

   Hi Claudia,
   No, I did not know the Pirates of Penzance.
   I have an uncle who is celebrating his 18th birthday tomorrow… since his father reached its 101st I would not be surprised he will reach 21st.
   :)
   Laurent

3. radino Says:
   February 28th, 2008 at 20:31

   nothing unexpected..

   doc:
   If date is the last day of the month or if the resulting month has fewer days than the day component of date, then the result is the last day of the resulting month.

4. Laurent Schneider Says:
   February 28th, 2008 at 20:37

   nothing unexpected if you read the doc before using add_months

5. Anonymous Says:
   February 29th, 2008 at 11:11

   If I was born Feb 28, 1990. Today is my birth day for 18 years old.

   ADD_MONTH
   ———
   27-FEB-08

   SQL> select add_months(date ‘1990-02-28′,18*12) from dual;

   ADD_MONTH
   ———
   29-FEB-08

6. HunterX Says:
   February 29th, 2008 at 12:11

   OK!
   I can watch adult movie or drink Gin-tonic.

   create function add_mon (date1 IN DATE,add_mon IN NUMBER) return DATE IS loc_date2 date;

   BEGIN
   loc_date2:= ADD_MONTHS(date1-1,add_mon);

   IF LAST_DAY(date1) = date1
   THEN
   IF LAST_DAY(loc_date2)=loc_date2
   THEN
   RETURN loc_date2;
   ELSE
   RETURN loc_date2 +1;
   END IF;
   ELSE
   RETURN ADD_MONTHS(date1,add_mon);
   END IF;

   END;
   /

   SQL> l
   1 declare
   2 a date;
   3 begin
   4 a := add_mon (to_date(’1990-02-28′,’YYYY-MM-DD’),18*12);
   5 dbms_output.put_line(a);
   6* end;
   SQL> /
   28-FEB-08

7. Laurent Schneider Says:
   February 29th, 2008 at 15:07

   not sure if you can enter the party when born 29-FEB-1991 next year before 1st march… depends on the bodyguard

8. Laurent Schneider Says:
   March 4th, 2008 at 14:14

   of course my comment is not very accurate… I mean if you are born 29-feb-1992 you will not be 18 on feb-28-2010 but one day later

9. HunterX Says:
   March 26th, 2008 at 10:22

   :-)

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