oracle sales total query - sql

Question

in a project i work at the moment we need to get monthly, quarterly and yearly sums of customer sales. i tried a query shown below which gets correct results for today. but i need to results for last years sale also. (last years monthly sale is that months sum)
i really need a fast fix here, thanks for every comment in advance
SELECT
CUSTOMER,
PRODUCT,
EXTRACT(MONTH FROM DAY) MONTH,
EXTRACT(YEAR FROM DAY) YEAR,
SUM(
CASE
WHEN DAY >= TRUNC(sysdate,'MM')
THEN DAILY_SALE
ELSE 0
END) AS MONTH_SALE,
SUM(
CASE
WHEN DAY >= add_months(TRUNC(sysdate,'MM'),-3)
AND DAY < TRUNC(sysdate,'MM')
THEN DAILY_SALE
ELSE 0
END) AS THREE_MONTHL_SALE,
SUM(
CASE
WHEN DAY >= add_months(TRUNC(sysdate,'MM'),-6)
AND DAY < TRUNC(sysdate,'MM')
THEN DAILY_SALE
ELSE 0
END) AS SIX_MONTHL_SALE,
SUM(
CASE
WHEN DAY >= add_months(TRUNC(sysdate,'MM'),-12)
AND DAY < TRUNC(sysdate,'MM')
THEN DAILY_SALE
ELSE 0
END) AS YEAR_SALE
FROM
SALES_TABLE
GROUP BY
CUSTOMER,
PRODUCT,
EXTRACT(MONTH FROM DAY),
EXTRACT(YEAR FROM DAY)

Answer 1

This may help be what you want... it gives you totals for every month and quarter, and for the entire year, for every year. I would recommend adding a "where EXTRACT(YEAR FROM DAY) = 2012" or similar clause if you want a particular year.
I believe this is what you asked for, but that is different than the sample you provided. The sample you gave provided trailing 3, 6, 9, and 12 month sales, which is not the same as quarters years and months. Still, you could easily mix and match if needed.
SELECT
CUSTOMER,
PRODUCT,
EXTRACT(YEAR FROM DAY) YEAR,
SUM(DAILY_SALE) as YEAR_SALES,
SUM(CASE WHEN TO_CHAR(DAY, 'MM') = '01' THEN DAILY_SALE ELSE 0 END) AS MONTH_01_SALES,
SUM(CASE WHEN TO_CHAR(DAY, 'MM') = '02' THEN DAILY_SALE ELSE 0 END) AS MONTH_02_SALES,
SUM(CASE WHEN TO_CHAR(DAY, 'MM') = '03' THEN DAILY_SALE ELSE 0 END) AS MONTH_03_SALES,
SUM(CASE WHEN TO_CHAR(DAY, 'MM') = '04' THEN DAILY_SALE ELSE 0 END) AS MONTH_04_SALES,
SUM(CASE WHEN TO_CHAR(DAY, 'MM') = '05' THEN DAILY_SALE ELSE 0 END) AS MONTH_05_SALES,
SUM(CASE WHEN TO_CHAR(DAY, 'MM') = '06' THEN DAILY_SALE ELSE 0 END) AS MONTH_06_SALES,
SUM(CASE WHEN TO_CHAR(DAY, 'MM') = '07' THEN DAILY_SALE ELSE 0 END) AS MONTH_07_SALES,
SUM(CASE WHEN TO_CHAR(DAY, 'MM') = '08' THEN DAILY_SALE ELSE 0 END) AS MONTH_08_SALES,
SUM(CASE WHEN TO_CHAR(DAY, 'MM') = '09' THEN DAILY_SALE ELSE 0 END) AS MONTH_09_SALES,
SUM(CASE WHEN TO_CHAR(DAY, 'MM') = '10' THEN DAILY_SALE ELSE 0 END) AS MONTH_10_SALES,
SUM(CASE WHEN TO_CHAR(DAY, 'MM') = '11' THEN DAILY_SALE ELSE 0 END) AS MONTH_11_SALES,
SUM(CASE WHEN TO_CHAR(DAY, 'MM') = '12' THEN DAILY_SALE ELSE 0 END) AS MONTH_12_SALES,
SUM(
CASE
WHEN TO_CHAR(DAY, 'MM') IN ('10', '11', '12')
THEN DAILY_SALE
ELSE 0
END) AS Q4_SALES,
SUM(
CASE
WHEN TO_CHAR(DAY, 'MM') IN ('07', '08', '09')
THEN DAILY_SALE
ELSE 0
END) AS Q3_SALES,
SUM(
CASE
WHEN TO_CHAR(DAY, 'MM') IN ('04', '05', '06')
THEN DAILY_SALE
ELSE 0
END) AS Q2_SALES,
SUM(
CASE
WHEN TO_CHAR(DAY, 'MM') IN ('01', '02', '03')
THEN DAILY_SALE
ELSE 0
END) AS Q1_SALES,
FROM
SALES_TABLE
GROUP BY
CUSTOMER,
PRODUCT,
EXTRACT(YEAR FROM DAY)

Answer 2

This may not be exactly what you need but it may help:
select a.Product_Name,
d.Company_Name,
to_char(Order_Date, 'YYYY') as OrderYear,
sum(case to_char(c.Order_Date, 'Q') when '1'
then b.Unit_Price*b.Quantity*(1-b.Discount) else 0 end) "Qtr 1",
sum(case to_char(c.Order_Date, 'Q') when '2'
then b.Unit_Price*b.Quantity*(1-b.Discount) else 0 end) "Qtr 2",
sum(case to_char(c.Order_Date, 'Q') when '3'
then b.Unit_Price*b.Quantity*(1-b.Discount) else 0 end) "Qtr 3",
sum(case to_char(c.Order_Date, 'Q') when '4'
then b.Unit_Price*b.Quantity*(1-b.Discount) else 0 end) "Qtr 4"
from Products a
....
Also, look here for good examples of what you may need:
http://docs.oracle.com/html/B13915_04/appendix.htm#BEHJBJDE