Last date in quarter MySQL - mysql

Question

I have a table with some dates. I need a query which will return the max (last) date from this table and last date of quarter this max date belongs to.
So for data i table
ID| EDATE
--+----------
1|2014-03-06
2|2014-10-12
this query should return 2014-10-12 and 2014-12-31.

Answer 1

As I understand you want the last day of the quarter, so 31 March, 30 June, 30 Sept, 31 Dec? So you can use the answer from Gordon Linoff and adjust it to do that.
You only need a case statement on month(date) and concat that with the year.
http://dev.mysql.com/doc/refman/5.1/de/control-flow-functions.html
str_to_date(
concat(
year(edate),
(case
when month(edate) in (1, 2, 3) then '-03-31'
when month(edate) in (4, 5, 6) then '-06-30'
when month(edate) in (7, 8, 9) then '-09-30'
else '-12-31'
end)
),
'%Y-%m-%d'
)

Answer 2

Getting the day of the last quarter for the date is a bit yucky, but possible. Here is a sort of brute force solution:
select edate,
str_to_date(concat(year(edate), '-', 1 + floor((month(edate) - 1)/ 3)) * 3, '-',
(case when month(edate) in (1, 2, 3, 10, 11, 12) then 31 else 30 end)),
'%Y-%m-%d'
)
from table t
order by edate desc
limit 1;
Here is a SQL Fiddle that demonstrates it.

Answer 3

You can use LAST_DAY to select the last day of a specific month depending on where your quarters end you may have to change the 3,6,9,12 to different months.
select t1.max_date,
(
case
when month(max_date) <= 3
then last_day(concat(year(max_date),'-3-1'))
when month(max_date) <= 6
then last_day(concat(year(max_date),'-6-1'))
when month(max_date) <= 9
then last_day(concat(year(max_date),'-9-1'))
else last_day(concat(year(max_date),'-12-1'))
end
) last_quarter_day
from (
select max(EDATE) max_date from myTable
) t1

Answer 4

I found the simplest answer:
SELECT MAKEDATE(YEAR(edate),1)
+ INTERVAL QUARTER(edate) QUARTER
- INTERVAL 1 DAY
This query takes the first day of year, adds quarters to it and subtracts 1 day to get the last day in wanted quarter. So the required query should look like:
SELECT MAX(edate),
MAKEDATE(YEAR(MAX(edate)),1)
+ INTERVAL QUARTER(MAX(edate)) QUARTER
- INTERVAL 1 DAY
FROM table