Extracting dates problem

Question

customer table
===========
customer_id varchar2(6)
st_dt date
ed_dt date
dop varchar2(7)
data
===
customer_id st_dt ed_dt dop
429100 2005/02/23 2006/03/20 0000007
customer1 table
============
customer_id varchar2(6)
st_dt date
ed_dt date
dop varchar2(7)
dt date
insert into customer1(customer_id, st_dt, ed_dt, dop, dt)
select a.customer_id, a.st_dt, a.ed_dt, a.dop, a.st_dt+b.tita
from customer a, (select rownum-1 tita from user_objects) b
where a.st_dt+b.tita <= a.ed_dt
and instr(a.dop, decode(to_char(a.st_dt+b.tita, 'd')-1,0,7,to_char(
a.st_dt+b.tita,'d')-1))>0
order by a.customer_id,a.st_dt+b.tita
The purpose of thie query is to extract all the dates in the customer table st_dt to ed_dt fields based on the field dop, 0000007 indicates Sunday, if the value is 1004007, it indicates monday, thursday and sunday. The results will insert into customer1 table, however the results are different if I execute the same query on different machine, they both run on oracle 10g database.
If i change st_dt to 2005/02/23 and ed_dt to 2005/03/20, it returns the right result, it seems that the ed_dt doesn't work if I change the year to 2006.
what's wrong with this query ? or is there something to do with the date settings in my database ?
thanks.

Answer 1

(select rownum-1 tita from user_objects) bInteresting way of creating a counter :)
Anyways, I guess you should not pick a date range that span more days than you have objects in your schema. You can possibly extend the range by selecting from all_objects instead :-)))))