Is this T-SQL query correct? - tsql

Question

My code returns a data set, however I do not believe they are accurate and I'm a bit lost working with sub queries. Can someone look over my code. The problem I'm trying to solve is from advanced question from T-SQL 2012 book. The question tells me:
Get the order ID, order date, customer ID, and company name for all orders that contain at least one item from the Condiments category. Use the category name in your query.
This is my code:
SELECT
o.orderid, o.orderdate, o.custid, c.companyname
FROM
Sales.Orders AS o
JOIN
Sales.OrderDetails AS od ON o.orderid = od.orderid
JOIN
Sales.Customers AS c ON o.custid = c.custid
WHERE
qty > 1
(SELECT categoryname FROM
Production.Categories
WHERE categoryname = N'Condiments');
My results:
orderid orderdate custid companyname
-------------------------------------------------------
10248 2006-07-04 00:00:00.000 85 Customer ENQZT
10248 2006-07-04 00:00:00.000 85 Customer ENQZT
10249 2006-07-05 00:00:00.000 79 Customer FAPSM
10250 2006-07-08 00:00:00.000 34 Customer IBVRG
Table structure:
Customers:
Sales.Customers
(
custid INT NOT NULL IDENTITY,
companyname NVARCHAR(40) NOT NULL,
contactname NVARCHAR(30) NOT NULL,
contacttitle NVARCHAR(30) NOT NULL
)
PK custid
Orders:
Sales.Orders
(
orderid INT NOT NULL IDENTITY,
custid INT NULL,
empid INT NOT NULL,
orderdate DATETIME NOT NULL
)
PK orderid
FK custid
Categories:
Production.Categories
(
categoryid INT NOT NULL IDENTITY,
categoryname NVARCHAR(15) NOT NULL,
description NVARCHAR(200) NOT NULL,
CONSTRAINT PK_Categories PRIMARY KEY(categoryid)
);
Orderdetails:
Sales.OrderDetails
(
orderid INT NOT NULL,
productid INT NOT NULL,
unitprice MONEY NOT NULL
CONSTRAINT DFT_OrderDetails_unitprice DEFAULT(0),
qty SMALLINT NOT NULL
)
I'm wrecking my head as this must be a correlated query because the Category table shares no relationship with Orders or Customers. Much appreciated for all learning/teaching responses.

Answer 1

There we go, your query should include the Products table, something like this:
SELECT o.orderid, o.orderdate, o.custid, c.companyname
FROM Sales.Orders AS o
JOIN Sales.OrderDetails AS od
ON o.orderid = od.orderid
JOIN Sales.Customers AS c
ON o.custid = c.custid
JOIN Production.Products d
on od.ProductId = d.ProductId
JOIN Production.Categories cat
on cat.CategoryId = d.CategoryID
and cat.categoryname = N'Condiments');
This may be enough to get you started.