how i can use Distinct in Query with INNER JOIN - sql

Question

I have a query from my products and factors and factor items for show them.
In this query I'm showing a report from factor for user.
My query is :
WITH CTE AS
(
SELECT
ROW_NUMBER() OVER (ORDER BY FactoriTems.datesave ASC) AS rn,
FactoriTems.code, FactoriTems.replacement,
FactoriTems.suggcode, Factors.dateexport,
Productions.descriptions,
FactoriTems.countt, FactoriTems.price,
FactoriTems.countt * FactoriTems.price AS 'total',
Productions.country
FROM
Productions
INNER JOIN
FactoriTems ON Productions.code = FactoriTems.code
INNER JOIN
Factors ON Factors.gid = FactoriTems.gid
WHERE
(FactoriTems.gid = #gid)
)
SELECT *
FROM CTE
ORDER BY rn
This query is OK, but there is a problem, in Productions table some category have two or three product with one code, and when this codes are in factoritems table show two rows in my result set!
Result is :
rn
code
dateexport
descriptions
countt
price
total
1
aaa
12/24/2021
...
100
2
200
2
bbb
12/24/2021
...
200
3
600
3
ccc
12/24/2021
...
100
2
200
4
ddd
12/24/2021
...
200
3
600
5
ddd
12/24/2021
...
100
2
200
6
eee
12/24/2021
...
200
3
600
Now how can I show only one row for 'ddd' product code?
I tried to use DISTINCT but I got an error.
I want the output to be as follows:
rn
code
dateexport
descriptions
countt
price
total
1
aaa
12/24/2021
...
100
2
200
2
bbb
12/24/2021
...
200
3
600
3
ccc
12/24/2021
...
100
2
200
4
ddd
12/24/2021
...
200
3
600
5
eee
12/24/2021
...
200
3
600
Thanks

Answer 1

Just missing PARTITIN BY clause for the code column within the inner query. Rewrite your current query such as
WITH CTE AS
(SELECT ROW_NUMBER() OVER (PARTITION BY ft.code ORDER BY ft.datesave) AS rn0,
ft.code,
ft.replacement,
ft.suggcode,
f.dateexport,
p.descriptions,
ft.countt,
ft.price,
ft.countt * ft.price AS total,
p.country
FROM Productions p
JOIN FactoriTems ft
ON p.code = ft.code
JOIN Factors f
ON f.gid = ft.gid
WHERE (ft.gid = #gid))
SELECT ROW_NUMBER() OVER (ORDER BY datesave,code) AS rn,
code, replacement, suggcode, dateexport, descriptions,
countt, price, total, country
FROM CTE
WHERE rn0 = 1
ORDER BY rn
in order to filter out the duplicates for each distinct grouped code

Answer 2

Try this code:
WITH CTE AS
(SELECT ROW_Number() over (PARTITION BY FactoriTems.code ORDER by FactoriTems.datesave ASC) as rn,FactoriTems.code,
FactoriTems.replacement, FactoriTems.suggcode,Factors.dateexport,
Productions.descriptions, FactoriTems.countt, FactoriTems.price,
FactoriTems.countt * FactoriTems.price AS 'total', Productions.country
FROM Productions
INNER JOIN FactoriTems ON Productions.code = FactoriTems.code
INNER JOIN Factors ON Factors.gid = FactoriTems.gid
WHERE (FactoriTems.gid = #gid))
SELECT * FROM CTE
WHERE CTE.rn = 1
ORDER BY rn