calendar.sql

From: Oradba Linux <techiey2k3_at_comcast.net>
Date: Mon, 22 Nov 2004 05:19:06 GMT
Message-ID: <eFeod.652457$8_6.498621@attbi_s04>

From connor mcdonald's mastering oracle pl/sql , i am not able to understand the logic for using the colum p. The query is below.

select

max(decode(dow,1,d,null)) Sun,
max(decode(dow,2,d,null)) Mon,
max(decode(dow,3,d,null)) Tue,
max(decode(dow,4,d,null)) Wed,
max(decode(dow,5,d,null)) Thu,
max(decode(dow,6,d,null)) Fri,
max(decode(dow,7,d,null)) Sat

from (
select rownum d ,

rownum-2+to_number(to_char(trunc(to_date('&CALDATE','DD-MON-YYYY'),'MM'),'D'
))p,

        to_char(trunc(to_date('&CALDATE','DD-MON-YYYY'),'MM')-1+rownum,'D') dow
from all_objects
where rownum <=to_number(to_char(last_day(to_date(sysdate)),'DD'))
)

group by trunc(p/7)
/ Received on Sun Nov 21 2004 - 23:19:06 CST