BUG #1066: avg(age()) results months with more than 30 days - Mailing list pgsql-bugs

From PostgreSQL Bugs List
Subject BUG #1066: avg(age()) results months with more than 30 days
Date
Msg-id 20040125092018.D392ACF4A30@www.postgresql.com
Whole thread Raw
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The following bug has been logged online:

Bug reference:      1066
Logged by:          Beda Szukics

Email address:      beda@muri-gries.ch

PostgreSQL version: 7.3.4

Operating system:   linux

Description:        avg(age()) results months with more than 30 days

Details:

Hello all

When I try to calculate the average age of the following birthdates I get
months with more than 30 days. Is this a bug?

I use version 7.3.4

These are the birthdates:


kongregation=> SELECT geb_dat FROM personen;
  geb_dat
------------
 20.12.1946
 29.01.1948
 21.03.1933
 07.01.1954
 22.08.1959
 07.07.1913
 30.11.1922
 29.08.1925
 07.01.1927
 06.07.1928
 25.09.1928
 23.05.1929
 25.04.1930
 27.03.1933
 21.12.1933
 28.03.1937
 03.02.1940
 13.12.1941
 13.02.1942
 30.04.1937
 25.08.1943
 03.06.1964
 26.01.1956
 04.11.1957
 27.12.1961
 22.03.1911
 30.11.1918
 02.05.1957
 08.03.1925
(29 rows)



Today (20.1.2004 german style) I get the answer:

kongregation=> SELECT AVG(AGE(geb_dat)) FROM personen ;
                avg
------------------------------------
 @ 65 years 9 mons 4 days 0.00 secs
(1 row)


Yesterday and the day before yesterday I got:

kongregation=> SELECT AVG(AGE('19.01.2004',geb_dat)) FROM personen ;
                         avg
------------------------------------------------------
 @ 65 years 8 mons 32 days 2 hours 28 mins 57.93 secs
(1 row)

kongregation=> SELECT AVG(AGE('20.01.2004',geb_dat)) FROM personen ;
                         avg
-----------------------------------------------------
 @ 65 years 8 mons 33 days 1 hour 39 mins 18.62 secs
(1 row)


BTW: I think having the result with years and days only would be a better
answer, what kind of months are counted in the present form?

Greetings                   Beda

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