get continuosly increasing sale records from table sql server - sql

Question

I have 2 tables
Product
ProdId, ProdName
1 A
2 B
and
Sale
SaleId, ProdId, Sale, Year
1, 1, 100, 2012
2, 1, 130, 2013
3, 2, 100, 2012,
4, 1, 150, 2014,
5, 1, 180, 2015
6, 2, 120, 2013,
7, 2, 90, 2014,
8, 2, 130, 2015
I want the name of product whose sale is continuosly increasing.
Like Product "A" has sale record like in year 2012 - 100 Units,2013 - 130 Units,2014 - 150 Units,2015 - 180 Units, So this product A is having continuous increase in sale. Another case of non-continuous record is, product "B" having sale record 2012 - 100 Units,2013 - 120 Units,2014 - 90 Units, 2015 - 130 Units, So for product "B", it is not continuous.
I want records like product "A", who is having continuous increasing sale.
Help appreciated.

Answer 1

You can do this using row_number() twice:
select prod_id
from (select s.*,
row_number() over (partition by s.prod_id order by sale) as seqnum_s,
row_number() over (partition by s.prod_id order by year) as seqnum_y
from sales s
) s
group by prod_id
having sum( case when seqnum_s = seqnum_y then 1 else 0 end) = count(*);
That is, order by the year and the sales. When all row numbers are the same, then the sales are increasing.
Note: There are some cases where tied sales might be considered increasing. This can be handled by the logic -- either by excluding or including such situations. I have not included logic for this, because your question is not clear what to do in that situation.

Answer 2

Use cross apply to get the previous year's sale amount and check with conditional aggregation for the increasing amount condition.
select prodid
from sale s1
cross apply (select sale as prev_sale
from sale s2
where s1.prodid=s2.prodid and s2.year=s1.year-1) s2
group by prodid
having sum(case when sale-prev_sale<0 then 1 else 0 end) = 0
To get the all the rows for such prodId's, use
select * from sale
where prodid in (select prodid
from sale s1
cross apply (select sale as prev_sale
from sale s2
where s1.prodid=s2.prodid and s2.year=s1.year-1) s2
group by prodid
having sum(case when sale-prev_sale<0 then 1 else 0 end) = 0
)

Answer 3

Here's a way with a CTE
declare #sale table (SaleID int, ProdId int, Sale int, Year int)
insert into #sale
values
(1,1,100,2012),
(2,1,130,2013),
(3,2,100,2012),
(4,1,150,2014),
(5,1,180,2015),
(6,2,120,2013),
(7,2,90,2014),
(8,2,130,2015)
declare #product table (ProdID int, ProdName char(1))
insert into #product
values
(1,'A'),
(2,'B')
;with cte as(
select
row_number() over (partition by ProdId order by Year) as RN
,*
from #sale)
select
p.ProdName
,cte.*
from cte
inner join
#product p on
p.ProdID=cte.ProdId
where cte.ProdId IN
(select distinct
c1.ProdId
from cte c1
left join
cte c2 on c2.RN = c1.rn+1 and c2.ProdId = c1.ProdId
group by c1.ProdId
having min(case when c1.Sale < isnull(c2.Sale,999999) then 1 else 0 end) = 1)
RETURNS
+----------+----+--------+--------+------+------+
| ProdName | RN | SaleID | ProdId | Sale | Year |
+----------+----+--------+--------+------+------+
| A | 1 | 1 | 1 | 100 | 2012 |
| A | 2 | 2 | 1 | 130 | 2013 |
| A | 3 | 4 | 1 | 150 | 2014 |
| A | 4 | 5 | 1 | 180 | 2015 |
+----------+----+--------+--------+------+------+