Reputation: 269
I am currently working on oracle sql and have some issues managing dates and quarters.
The first thing I try to do is given a quarter and a year I would like to know the number of days of the quarter. For example, quarter 1 in 2013 had 90 days but in 2012 had 91 days.
The second thing I would like to do is convert a date dd/qq/yyyy to a date dd/mm/yyyy.
For instance, 60/2/2013 gives 30/5/2013. I am a beginner in Oracle so any help or function names will be highly appreciated.
Thanks
Upvotes: 4
Views: 13723
Reputation: 23588
For your first question, hopefully this will give you some idea of what to do:
with sample_data as (select 2012 yr, 1 quarter from dual union all
select 2012 yr, 2 quarter from dual union all
select 2012 yr, 3 quarter from dual union all
select 2012 yr, 4 quarter from dual union all
select 2013 yr, 1 quarter from dual union all
select 2013 yr, 2 quarter from dual)
---- end of mimicking a table called "sample_data"; see query below:
select yr,
quarter,
add_months(to_date('01/01/'||yr, 'dd/mm/yyyy'), (quarter - 1)*3) qtr_st,
add_months(to_date('01/01/'||yr, 'dd/mm/yyyy'), quarter * 3) - 1 qtr_end,
add_months(to_date('01/01/'||yr, 'dd/mm/yyyy'), quarter * 3) - add_months(to_date('01/01/'||yr, 'dd/mm/yyyy'), (quarter - 1)*3) diff
from sample_data;
YR QUARTER QTR_ST QTR_END DIFF
---------- ---------- ---------- ---------- ----------
2012 1 01/01/2012 31/03/2012 91
2012 2 01/04/2012 30/06/2012 91
2012 3 01/07/2012 30/09/2012 92
2012 4 01/10/2012 31/12/2012 92
2013 1 01/01/2013 31/03/2013 90
2013 2 01/04/2013 30/06/2013 91
N.B. Because you're including the day of the start_date in the count, the difference is effectively how many days between the 1st of the quarter and the 1st of the next quarter, or qtr_end - qtr_st + 1
from my query above.
For your second question, here's one way:
with sample_data as (select '60/2/2013' dy_qtr_fmt from dual union all
select '60/02/2013' dy_qtr_fmt from dual union all
select '01/1/2013' dy_qtr_fmt from dual union all
select '1/1/2013' dy_qtr_fmt from dual)
---- end of mimicking a table called "sample_data"; see query below:
select dy_qtr_fmt,
add_months(year_st, (qtr-1)*3) + num_days_in_qtr - 1 dt
from (select dy_qtr_fmt,
to_date('01/01/'||substr(dy_qtr_fmt, -4), 'dd/mm/yyyy') year_st,
to_number(substr(dy_qtr_fmt, instr(dy_qtr_fmt, '/', 1, 1) + 1, instr(dy_qtr_fmt, '/', 1, 2) - instr(dy_qtr_fmt, '/', 1, 1) -1)) qtr,
to_number(substr(dy_qtr_fmt, 1, instr(dy_qtr_fmt, '/', 1, 1) - 1)) num_days_in_qtr
from sample_data);
DY_QTR_FMT DT
---------- ----------
60/2/2013 30/05/2013
60/02/2013 30/05/2013
01/1/2013 01/01/2013
1/1/2013 01/01/2013
Upvotes: 1
Reputation: 2115
this gives the number of days in the current quarter, playing around with the add_months should allow you to find the length of other quarters
select (add_months(trunc(sysdate,'q'),3) - 1) - trunc(sysdate,'q')
from dual;
Upvotes: 2