I have 3 same product in ID=42, with 3 different images. I want to take the first image from the product ID, I try adding "TOP 1", error
This is my query
CREATE OR REPLACE VIEW UserOrdersView
AS
SELECT
u.[User_ID],
p.Product_Name,
p.Price,
o.Order_Price,
o.Order_ID,
i.[Image]
FROM Product p
LEFT JOIN Orders o ON o.Product_ID = p.Product_ID
INNER JOIN Users u ON u.[User_ID]= o.[User_ID]
LEFT JOIN Product_Images i ON i.Product_ID = p.Product_ID
WHERE o.[User_ID] = 42
You need to use OUTER APPLY to get top 1 image data from Product_image table based on Product ID.
Please check this Real life example, when to use OUTER / CROSS APPLY in SQL stackoverflow link for more knowledge.
Please check below updated view code for your answer.
CREATE OR REPLACE VIEW UserOrdersView
AS
BEGIN
SELECT
u.[User_ID],
p.Product_Name,
p.Price,
o.Order_Price,
o.Order_ID,
i.[Image]
FROM Product p
INNER JOIN Users u ON u.[User_ID]= o.[User_ID]
LEFT JOIN Orders o ON o.Product_ID = p.Product_ID
OUTER APPLY
(
SELECT TOP 1
T2.[Image]
FROM Product_Images T2
WHERE T2.Product_ID = p.Product_ID
) i
WHERE o.[User_ID] = 42
END
GO
WITH cte as (
SELECT
u.[User_ID],
p.Product_Name,
p.Price,
o.Order_Price,
o.Order_ID,
i.[Image],
ROW_NUMBER() OVER (PARTITION BY i.[Image] ORDER BY p.Product_Name) AS rn
FROM Product p
LEFT JOIN Orders o ON o.Product_ID = p.Product_ID
INNER JOIN Users u ON u.[User_ID]= o.[User_ID]
LEFT JOIN Product_Images i ON i.Product_ID = p.Product_ID
)
SELECT [User_ID],Product_Name,Price,Order_Price,Order_ID,[Image] FROM cte
WHERE rn=1
Put your all query inside a CTE with a new column that you will use to filter the results.
This new column is produced with ROW_NUMBER() function partitioned by Product_Name
Related
SELECT i.product_id, o.date_added
FROM ims_order_product i
INNER JOIN ims_order o
WHERE i.product_id IN (SELECT p.product_Id FROM ims_product p)
The Query Return Product_id column and Date column But Product_id column contain duplicates So I want remove duplicates in Product_id based on Date_added by recent Date Can any give the answer.
Try grouping by product_id. Below query will select the latest date for duplicate product_id
SELECT i.product_id, MAX(o.date_added) FROM ims_order_product i INNER JOIN ims_order o WHERE i.product_id IN (SELECT p.product_Id FROM ims_product p) GROUP BY i.product_id
Please try this query
SELECT i.product_id, MAX(o.date_added) date_added
FROM ims_order_product i
INNER JOIN ims_order o --add your join condition here
WHERE EXISTS (SELECT p.product_Id FROM ims_product p WHERE p.product_Id = i.product_id)
GROUP BY i.product_id
SELECT * FROM (SELECT i.product_id, o.date_added, o.order_id FROM ims_order_product i
JOIN ims_order o ON o.order_id = i.order_id
JOIN ims_product pr ON pr.product_id = i.product_id ORDER BY date_added DESC) AS sub GROUP BY product_id
I have a query something like
SELECT S.product_id, S.link, C.id AS category_id
FROM Products P
INNER JOIN SEO S ON S.product_id = P.id AND P.product_type = 1
LEFT OUTER JOIN Categories C ON c.product_id = P.id
WHERE P.active = 1
I works fine for me as long as each product has assigned to only one category. But if a product is assigned to many categories it returns all possible combinations.
Can I only select the first one and if a product don't have any category the link should still be returned with category_id = NULL
An easy way is to use outer apply, so as to have a correlated join, and make that a top 1 query. Thus you are able to access all columns of the category record in question. I'm adding a category name here as an example:
select s.product_id, s.link, c.id as category_id, c.name as category_name
from products p
inner join seo s on s.product_id = p.id
outer apply
(
select top 1 *
from categories cat
where cat.product_id = p.id
order by cat.id
) c
where p.active = 1
and p.product_type = 1;
You can use a GROUP BY to accomplish this along with an Aggregate function, most likely MIN or MAX.
Depending on which Category Id you prefer in your result you could select the minimum.
SELECT S.product_id, S.link, MIN(C.id) AS category_id
FROM Products P
INNER JOIN SEO S ON S.product_id = P.id AND P.product_type = 1
LEFT OUTER JOIN Categories C ON c.product_id = P.id
WHERE P.active = 1
GROUP BY S.product_id, S.link
Or the maximum.
SELECT S.product_id, S.link, MAX(C.id) AS category_id
FROM Products P
INNER JOIN SEO S ON S.product_id = P.id AND P.product_type = 1
LEFT OUTER JOIN Categories C ON c.product_id = P.id
WHERE P.active = 1
GROUP BY S.product_id, S.link
Alternate solution using subquery:
SELECT S.product_id, S.link,
(
SELECT C.id FROM Categories C WHERE C.product_id = P.id AND
ROW_NUMBER() OVER(ORDER BY /* your sort option goes here*/ ) = 1
) AS category_id
FROM Products P
INNER JOIN SEO S ON S.product_id = P.id AND P.product_type = 1
WHERE P.active = 1
Each product in the database can have many revisions. Some products might not have any revisions at all.
ProductRevision table has the following fields: Id, Version, SubmitDate
I am trying to figure out how I can select a field called LatestRevisionId based on the MAX SubmitDate and if not revision then the field will be null
SELECT p.Id, p.Name, p.Price
FROM Product p
LEFT OUTER JOIN ProductRevision pr ON p.Id = pr.ProductId
Do I have to do a sub select in my select? I really want to try and use HAVING but can't figure out how to do it with a left join.
I was trying to do the following as a sub select:
(SELECT Id
FROM ProductRevision
WHERE ProductId=p.Id
HAVING SubmitDate=MAX(SubmitDate)
) AS LatestVersionId
Please note that I am using SQL SERVER 2008
Here's one option using row_number:
SELECT *
FROM (
SELECT p.Id, p.Name, p.Price, pr.id as LatestRevisionId,
row_number() over (partition by p.Id order by pr.SubmitDate desc) rn
FROM Product p
LEFT OUTER JOIN ProductRevision pr PN p.Id = pr.ProductId
) t
WHERE rn = 1
This will select a single Product with the latest matching row from the ProductRevision table.
If you just prefer to use max, then you need to join the table back to itself again:
SELECT p.Id, p.Name, p.Price, pr.id as LatestRevisionId
FROM Product p
LEFT OUTER JOIN ProductRevision pr PN p.Id = pr.ProductId
LEFT OUTER JOIN (SELECT ProductId, MAX(SubmitDate) MaxSubmitDate
FROM ProductRevision
GROUP BY ProductId) mpr ON pr.ProductId = mpr.ProductId AND
pr.SubmitDate = mpr.MaxSubmitDate
This could perhaps return duplicates though if multiple revisions share the same date.
if you are using SQL Server 2012 and aboe, below code will give you desired result.
SELECT DISTINCT p.Id, p.Name, p.Price, FIRST_VALUE(pr.ID) OVER (PARTITION BY p.Id ORDER BY pr.SubmitDate DESC) AS LatestVersionId
FROM Product p
LEFT OUTER JOIN ProductRevision pr ON p.Id = pr.ProductId
You can use a LEFT JOIN like this:
SELECT p.Id, p.Name, p.Price, pr.RevisionId as LatestRevisionId
FROM Product p LEFT OUTER JOIN
(SELECT pr.*,
ROW_NUMBER() OVER (PARTITION BY ProductId ORDER BY SubmitDate DESC) as seqnum
FROM ProductRevision pr
)
ON p.Id = pr.ProductId AND seqnum = 1;
If you want to aggregation other values, then just do:
SELECT p.Id, p.Name, p.Price,
MAX(CASE WHEN seqnum = 1 THEN pr.RevisionId END) as LatestRevisionId
FROM Product p LEFT OUTER JOIN
(SELECT pr.*,
ROW_NUMBER() OVER (PARTITION BY ProductId ORDER BY SubmitDate DESC) as seqnum
FROM ProductRevision pr
)
ON p.Id = pr.ProductId
GROUP BY p.Id, p.Name, p.Price;
This should be the simplest method to accomplish what you want.
I have two tables in my DB - products & orders. An order can only be of one kind of product.
Here's the basic idea:
What I'm trying to do is a query that given a copmany_id returns all the products (from that company) that have less than 10 orders (including 0)
my query looks like this:
SELECT p.*
FROM product p,
order o
WHERE p.company_id =?
AND o.product_id = p.id
GROUP BY p.id
HAVING Count(o.id) < 10
ORDER BY p.id DESC
The query works fine for products which have 0 < orders but doesn't return ones with 0 orders. What do I need to do to return them as well?
You're INNER JOINING your two tables, which means that only those products are returned for which there is at least one order.
You will need to LEFT OUTER JOIN the order table:
SELECT p.*
FROM product p
LEFT OUTER JOIN order o
ON o.product_id = p.id
WHERE p.company_id = ?
GROUP BY p.id
HAVING Count(o.id) < 10
ORDER BY p.id DESC
A left outer join will return every record on the left-hand side of the JOIN operation at least once, regardless if there is a matching record to the right-hand side of the JOIN operation.
try left outer join
SELECT p.*
FROM product p
LEFT OUTER JOIN order o
ON o.product_id = p.id
WHERE p.company_id =?
GROUP BY p.id
HAVING Count(o.id) < 10
ORDER BY p.id DESC
See this example for left outer join
Here is a simplified table structure:
TABLE products (
product_id INT (primary key, auto_increment),
category_id INT,
product_title VARCHAR,
etc
);
TABLE product_photos (
product_photo_id (primary key, auto_increment),
product_id INT,
photo_href VARCHAR,
photo_order INT
);
A product can have multiple photos, the first product photo for each product (based on the photo_order) is the default photo.
Now, I only need all of the photos on the product details page, but on pages where I am listing multiple products, for example a product directory page, I only want to display the default photo.
So what I am trying to do, is query a list of products including the default photo for each product.
This obviously doesn't work, it will return all photos with the product info duplicated for each photo:
SELECT p.*, ph.*
FROM products AS p
LEFT JOIN product_photos AS ph
ON p.product_id=ph.product_id
ORDER BY p.product_title ASC
I need to figure out how to do something like this, but I don't know the syntax (or if it is possible)
SELECT p.*, ph.*
FROM products AS p
LEFT JOIN product_photos AS ph
ON p.product_id=ph.product_id **ORDER BY ph.photo_order ASC LIMIT 1**
ORDER BY p.product_title ASC
Edit: I figured out a solution with help from the answers below, thanks all!
SELECT p.*, ph.*
FROM products AS p
LEFT JOIN product_photos AS ph
ON p.product_id=ph.product_id
AND ph.photo_order =
(
SELECT MIN(z.photo_order)
FROM product_photos AS z
WHERE z.product_id=p.product_id
)
GROUP BY p.product_id
ORDER BY p.product_title ASC
SELECT p.*, ph.*
FROM products AS p
INNER JOIN product_photos AS ph
ON p.product_id = ph.product_id
LEFT JOIN product_photos AS ph2
ON p.product_id = ph2.product_id
AND ph2.photo_order < ph.photo_order
WHERE ph2.photo_order IS NULL
ORDER BY p.product_title ASC
Note the how it joins to the product_photos table twice. The WHERE ph2.photo_order IS NULL will throw out all but the lowest photo order. It won't protect you against duplicate product_id / photo_orders combo though, you could add a GROUP BY on p.id if that's the case.
Use:
SELECT p.*,
pp.*
FROM PRODUCTS p
JOIN PRODUCT_PHOTOS pp ON pp.product_id = p.product_id
JOIN (SELECT x.product_id,
MIN(x.photo_order) AS default_photo
FROM PRODUCT_PHOTOS x
GROUP BY x.product_id) y ON y.product_id = pp.product_id
AND y.default_photo = pp.photo_order
SELECT p.*, ph.*
FROM products AS p
LEFT JOIN product_photos AS ph ON p.product_id=ph.product_id
ORDER BY p.product_title ASC, ph.photo_order ASC
GROUP BY p.product_id
LIMIT 0,10
SELECT ...
....
GROUP BY p.product_id