问题
I have a table one in which there are various attribute like region product,year,qtr,month,sale. I have to calculate the avg_qtr sale of each product having same region and show their previous avg_qtr sale.I have read about lag but here it is not possible to use as it is not fixed after how many rows it will be repeated. My table structure is like this
Region Product Year Qtr Month Sales
NORTH P1 2015 1 JAN 1000
NORTH P1 2015 1 FEB 2000
NORTH P1 2015 1 MAR 3000
NORTH P1 2015 2 APR 4000
NORTH P1 2015 2 MAY 5000
NORTH P1 2015 2 JUN 6000
NORTH P1 2015 3 JUL 7000
NORTH P1 2015 3 AUG 8000
NORTH P1 2015 3 SEP 9000
NORTH P1 2015 4 OCT 1000
NORTH P1 2015 4 DEC 4000
NORTH P1 2015 4 NOV 2000
NORTH P3 2015 1 FEB 1000
NORTH P3 2015 1 FEB 9000
NORTH P3 2015 2 APR 2000
NORTH P3 2015 3 JUL 8000
NORTH P1 2016 1 MAR 3000
NORTH P1 2016 1 FEB 1000
NORTH P1 2016 1 JAN 2000
SOUTH P1 2015 1 JAN 2000
SOUTH P1 2015 1 FEB 3000
SOUTH P1 2015 1 JAN 4000
SOUTH P2 2015 1 MAR 1000
SOUTH P2 2015 1 JAN 8000
SOUTH P2 2015 1 FEB 9000
SOUTH P2 2015 2 JUN 9000
SOUTH P2 2015 2 MAY 8000
SOUTH P2 2015 2 APR 2000
SOUTH P2 2015 3 SEP 4000
SOUTH P2 2015 3 AUG 2000
SOUTH P2 2015 3 JUL 1000
SOUTH P2 2015 4 NOV 2000
SOUTH P2 2015 4 DEC 1000
SOUTH P2 2015 4 OCT 5000
SOUTH P3 2015 3 AUG 9000
SOUTH P3 2015 4 OCT 1000
SOUTH P3 2015 4 NOV 3000
SOUTH P2 2016 1 JAN 2000
SOUTH P2 2016 1 JAN 4000
I wrote the query which calculates current qtr and is showing previous one avg with current one
WITH AvgSales
AS (SELECT
region,
product,
year,
qtr,
ROUND(AVG(sales), 2) AS avg_Sale
FROM one
GROUP BY region,
product,
year,qtr
)
SELECT
s.region,
s.product,
s.year,
s.month,
s.sales,
avg.qtr,
avg.avg_Sale AS Qtr_Avg_Sale,
prev.avg_sale AS Prev_Qtr_Avg_Sale
FROM one s
JOIN AvgSales avg
ON s.region = avg.region
AND s.product = avg.product
AND s.QTR = avg.qtr
AND s.year = avg.year
LEFT JOIN AvgSales prev
ON (s.region = prev.region
AND s.product = prev.product
AND s.year - 1 = prev.year
and s.qtr=1
AND prev.qtr = 4) or
(s.region = prev.region
AND s.product = prev.product
AND s.year = prev.year
AND s.qtr - 1 = prev.qtr) ;
I am able to get current average and previous average of that product but not vice versa. I am not sure how to show the previous average of that quarter which does not have any sale in current quarter. I want a output like this-
Region Product Year qtr month sale avg_Sale prev_avg_sale
NORTH P1 2015 1 JAN 1000 2000
NORTH P1 2015 1 FEB 2000 2000
NORTH P1 2015 1 MAR 3000 2000
NORTH P1 2015 2 APR 4000 5000 2000
NORTH P1 2015 2 MAY 5000 5000 2000
NORTH P1 2015 2 JUN 6000 5000 2000
NORTH P1 2015 3 JUL 7000 8000 5000
NORTH P1 2015 3 AUG 8000 8000 5000
NORTH P1 2015 3 SEP 9000 8000 5000
NORTH P1 2015 4 OCT 1000 2333.33 8000
NORTH P1 2015 4 NOV 2000 2333.33 8000
NORTH P1 2015 4 DEC 4000 2333.33 8000
SOUTH P2 2015 1 JAN 8000 6000
SOUTH P2 2015 1 FEB 9000 6000
SOUTH P2 2015 1 MAR 1000 6000
SOUTH P2 2015 2 APR 2000 6333.33 6000
SOUTH P2 2015 2 MAY 8000 6333.33 6000
SOUTH P2 2015 2 JUN 9000 6333.33 6000
SOUTH P2 2015 3 JUL 1000 2333.33 6333.33
SOUTH P2 2015 3 AUG 2000 2333.33 6333.33
SOUTH P2 2015 3 SEP 4000 2333.33 6333.33
SOUTH P2 2015 4 OCT 5000 2666.67 2333.33
SOUTH P2 2015 4 NOV 2000 2666.67 2333.33
SOUTH P2 2015 4 DEC 1000 2666.67 2333.33
NORTH P3 2015 1 FEB 9000 5000
NORTH P3 2015 1 FEB 1000 5000
NORTH P3 2015 2 APR 2000 2000 5000
NORTH P3 2015 3 JUL 8000 8000 2000
SOUTH P3 2015 3 AUG 9000 9000
SOUTH P3 2015 4 OCT 1000 2000 9000
SOUTH P3 2015 4 NOV 3000 2000 9000
NORTH P1 2016 1 JAN 2000 2000 2333.33
NORTH P1 2016 1 FEB 1000 2000 2333.33
NORTH P1 2016 1 MAR 3000 2000 2333.33
NORTH P2 2016 2 2000
SOUTH P2 2016 1 JAN 2000 3000 2666.67
SOUTH P2 2016 1 JAN 4000 3000 2666.67
SOUTH P2 2016 2 3000
SOUTH P1 2015 1 JAN 4000 3000
SOUTH P1 2015 1 JAN 2000 3000
SOUTH P1 2015 1 FEB 3000 3000
回答1:
You can use the windowing clause of an analytic function if you have a single ordered value to sort by, so first create a DENSE_RANKing of year and qtr, then use that ranking in your analytic functions:
with t1 as (
select one.*
, dense_rank() over (order by year, qtr) qord
from one
)
select product
, year
, qtr
, month
, sales
, round(avg(sales) over (partition by qord),2) qtr_avg
, round(avg(sales) over (order by qord
range between 1 preceding
and 1 preceding),2) prev_qtr_avg
from t1
The above solution assumes dense quarterly data as provided in the sample data set, if however, the data is sparse along the quarter dimension you can first densify the data as in this query:
with qtrs as (select level qtr from dual connect by level <=4)
, t1 as (
select product
, year
, qtrs.qtr
, month
, sales
, dense_rank() over (order by year, qtrs.qtr) qord
from qtrs
left outer join one partition by (year)
on one.qtr = qtrs.qtr
)
select product
, year
, qtr
, month
, sales
, round(avg(sales) over (partition by qord),2) qtr_avg
, round(avg(sales) over (order by qord
range between 1 preceding
and 1 preceding),2) prev_qtr_avg
from t1
This ensures that for every year represented in the data at least one row will exist for each quarter, and consequently QORD will enumerate every quarter, and gaps in the data will result in gaps in the calculated quarterly averages.
You can also achieve a similar effect by altering the way QORD is calculated by exploiting the numeric natures of YEAR and QTR as in this example:
with t1 as (select one.*, year*4+qtr qord from one)
select product
, year
, qtr
, month
, sales
, round(avg(sales) over (partition by qord),2) qtr_avg
, round(avg(sales) over (order by qord
range between 1 preceding
and 1 preceding),2) prev_qtr_avg
from t1
Here no densification was required, and yet it still correctly leaves gaps in the prev_qtr_avg, but it does leave out records for missing quarters which the densified data includes.
Combining the last two examples, and adding in your new requirement for regions a at least one row of data per quarter will be returned or generated if required for every distinct region, product and year. Both averages are partitioned by region and product and calculated per current or previous quarter as the case may be:
with qtrs(qtr) as (select level from dual connect by level <= 4)
, t1 as (
select region, product, year, q.qtr, month, sales, year*4+q.qtr qord
from qtrs q
left join one partition by (region, product, year)
on q.qtr = one.qtr
)
select region
, product
, year
, qtr
, month
, sales
, round(avg(sales) over (partition by region, product, qord),2) avg_sale
, round(avg(sales) over (partition by region, product
order by qord
range between 1 preceding
and 1 preceding),2) prev_avg_sale
from t1
order by year, region, qtr, product;
回答2:
Edited with the latest requirements.
Your problem is that you are trying to get the previous_avg by trying to manipulate QTR and YEAR. I'm using the RANK function, ordering the way I want the data ranked. In the joins I'm making sure that Average Region = Previous Region and disregarding year since the previous quarter could be Q4 of the Previous year for Average year Q1; it's cleaner this way.
--Build the test table
IF OBJECT_ID('SALES','U') IS NOT NULL
DROP TABLE SALES
CREATE TABLE SALES
(
Region VARCHAR(255)
, Product VARCHAR(10)
, [Year] INT
, QTR INT
, [Month] VARCHAR(19)
, Sales DECIMAL(19,4)
);
INSERT SALES
VALUES
('NORTH', 'P1', 2015, 1, 'JAN', 1000)
,('NORTH', 'P1', 2015, 1, 'FEB', 2000)
,('NORTH', 'P1', 2015, 1, 'MAR', 3000)
,('NORTH', 'P1', 2015, 2, 'APR', 4000)
,('NORTH', 'P1', 2015, 2, 'MAY', 5000)
,('NORTH', 'P1', 2015, 2, 'JUN', 6000)
,('NORTH', 'P1', 2015, 3, 'JUL', 7000)
,('NORTH', 'P1', 2015, 3, 'AUG', 8000)
,('NORTH', 'P1', 2015, 3, 'SEP', 9000)
,('NORTH', 'P1', 2015, 4, 'OCT', 1000)
,('NORTH', 'P1', 2015, 4, 'DEC', 4000)
,('NORTH', 'P1', 2015, 4, 'NOV', 2000)
,('NORTH', 'P3', 2015, 1, 'FEB', 1000)
,('NORTH', 'P3', 2015, 1, 'FEB', 9000)
,('NORTH', 'P3', 2015, 2, 'APR', 2000)
,('NORTH', 'P3', 2015, 3, 'JUL', 8000)
,('NORTH', 'P1', 2016, 1, 'MAR', 3000)
,('NORTH', 'P1', 2016, 1, 'FEB', 1000)
,('NORTH', 'P1', 2016, 1, 'JAN', 2000)
,('SOUTH', 'P1', 2015, 1, 'JAN', 2000)
,('SOUTH', 'P1', 2015, 1, 'FEB', 3000)
,('SOUTH', 'P1', 2015, 1, 'JAN', 4000)
,('SOUTH', 'P2', 2015, 1, 'MAR', 1000)
,('SOUTH', 'P2', 2015, 1, 'JAN', 8000)
,('SOUTH', 'P2', 2015, 1, 'FEB', 9000)
,('SOUTH', 'P2', 2015, 2, 'JUN', 9000)
,('SOUTH', 'P2', 2015, 2, 'MAY', 8000)
,('SOUTH', 'P2', 2015, 2, 'APR', 2000)
,('SOUTH', 'P2', 2015, 3, 'SEP', 4000)
,('SOUTH', 'P2', 2015, 3, 'AUG', 2000)
,('SOUTH', 'P2', 2015, 3, 'JUL', 1000)
,('SOUTH', 'P2', 2015, 4, 'NOV', 2000)
,('SOUTH', 'P2', 2015, 4, 'DEC', 1000)
,('SOUTH', 'P2', 2015, 4, 'OCT', 5000)
,('SOUTH', 'P3', 2015, 3, 'AUG', 9000)
,('SOUTH', 'P3', 2015, 4, 'OCT', 1000)
,('SOUTH', 'P3', 2015, 4, 'NOV', 3000)
,('SOUTH', 'P2', 2016, 1, 'JAN', 2000)
,('SOUTH', 'P2', 2016, 1, 'JAN', 4000);
--CTE TO CAPTURE AVG SALES BY REGION, PRODCUT, YEAR, QTR; OMIT PRODUCT IF YOU WANT STRAIGHT UP QUARTER AVG, REGARDLESS OF PRODCUCT
WITH cteAvgSales AS
(
SELECT Region, Product, [Year], QTR, AVG(Sales) current_avg
, RANK() OVER(ORDER BY Region, Product, [Year], QTR) AS RNK
FROM SALES
GROUP BY Region, Product, [Year], QTR
)
SELECT s.Region, s.Product, s.[Year] AS [year], s.QTR AS [quarter], s.[Month], s.Sales, a.current_avg, p.current_avg AS previous_avg
FROM SALES s
INNER JOIN cteAvgSales a ON a.Region = s.Region
AND a.Product = s.Product
AND a.[Year] = s.[Year]
AND a.QTR = s.QTR
LEFT JOIN cteAvgSales p ON p.Region = a.Region
AND p.Product = s.Product
AND p.RNK=a.RNK-1
ORDER BY s.Region, s.Product, s.[Year], s.QTR
回答3:
You need to join on some sub-select statements that will get the previous quarter avg. You will also need to do a union of two statements because for quarters 2,3,4 you can simply subtract a quarter on the join statement to the previous qtr avg, but when it is the 1st quarter you need to subtract a year and set the previous qtr = 4. This statement should work for what you have described.
--handles when the current quarter being viewed is 2,3,or 4 because those would still be in the same year when looking at the previous quarter
select t1.product,
t1.year,
t1.month,
t1.sales ,
t1.qtr,
round(avg(t1.sales) over (partition by t1.qtr,t1.year),2) as av,
t2.prev_av
from one t1
left join ( select
product,
year,
month,
sales ,
qtr,
round(avg(sales) over (partition by qtr,year),2) as prev_av
from one
) t2
on t1.year = t2.year
and (t1.qtr - 1) = t2.qtr
where t1.qtr in (2,3,4)
union
--handles the 1st quarter of the year when you need to grab the 4th quarter of the previous year for the previous avg
select t3.product,
t3.year,
t3.month,
t3.sales ,
t3.qtr,
round(avg(t3.sales) over (partition by t3.qtr,t3.year),2) as av,
t4.prev_av
from one t3
left join ( select
product,
year,
month,
sales,
qtr,
round(avg(sales) over (partition by qtr,year),2) as prev_av
from one
) t4
on (t3.year - 1) = t4.year
and t4.qtr = 4
where t3.qtr = 1;
来源：https://stackoverflow.com/questions/32349374/avg-sale-of-quarter-with-previous-quarter-avg-sale