Query That Returns First Results from Subquery - sql

Question

I'm trying to create a query that returns the results from a subquery in the result set.
Here are the tables I'm using:
Orders OrderDetails
------- -----------
orderId orderDetailId
(other data) orderId
productName
I'd like to get the first two order details for each order (Most orders have only one or two details). Here's an example of the desired result set:
orderId (other order data) productName1 productName2
------- ------------------ ------------ ------------
1 (other order data) apple grape
2 (other order data) orange banana
3 (other order data) apple orange
This is what I tried so far:
SELECT o.orderid,
Max(CASE WHEN detail = 1 THEN oi.productname END) AS ProductName1,
Max(CASE WHEN detail = 2 THEN oi.productname END) AS ProductName2
FROM orders AS o
OUTER apply (SELECT TOP 2 oi.*,
Row_number() OVER (ORDER BY orderdetailid) AS detail
FROM orderdetails AS oi
WHERE oi.orderid = o.orderid) AS oi
GROUP BY o.orderid
I'm doing this in the custom reporting module of a hosted ecommerce solution and getting the following unhelpful syntax error: SQL Error: Incorrect syntax near '('.
Unfortunately I don't know what version of SQL Server I'm using. Customer support knows nothing and select ##Version doesn't work.
Note, it appears the row_number() function is not properly supported even though error messages reference the function by name.
Thanks for the help!

Answer 1

Here is an alternative that does not use cross apply. Your ranking was correct but I added a partition by the order.
SELECT
*
FROM
(
SELECT
o.orderid,
ProductName=oi.productcode,
RowNumber=ROW_NUMBER() OVER (PARTITION BY o.orderid ORDER BY oi.orderdetailid)
FROM
orders as o
INNER JOIN orderdetailid oi ON oi.orderid=o.orderid
)AS X
WHERE
RowNumber=1
without using row_number
SELECT
orderdetails.*
Q1.*
FROM
(
SELECT
o.*,
FirstOrderDetailID=(SELECT MIN(orderdetails.orderdetailsid) FROM orderdetails WHERE orderid=o.orderid)
FROM
orders o
)AS Q1
LEFT OUTER JOIN orderdetails oi ON oi.orderdetailsid=Q1.FirstOrderDetailID

Answer 2

If you are just selecting orderid and the product, you don't need the join at all:
select orderid, productcode
from (SELECT oi.orderid, oi.productcode,
row_number() over (partition by oi.orderid order by oi.orderdetailid) as seqnum
FROM orderdetails oi
) oi
where seqnum = 1;
This may not fix the problem if row_number() is not working, but it simplifies the query. You can do this with the min() method as well:
select orderid, productcode
from orderdetails oi
where oi.orderdetailid in (select min(orderdetailid) from orderdetails group by orderid);