Selecting top 10 rows based on one column.

Question

Hi,
I need to display the top 10 records for each distinct value of a column. 

Answer 1

USE Northwind;
-- Solution 1
SELECT S.SupplierID, S.CompanyName, CA.ProductID, CA.UnitPrice
FROM dbo.Suppliers AS S
  CROSS APPLY
    (SELECT TOP (10) *
     FROM dbo.Products AS P
     WHERE P.SupplierID = S.SupplierID
     ORDER BY UnitPrice DESC, ProductID DESC) AS CA
ORDER BY S.SupplierID, CA.UnitPrice DESC, CA.ProductID DESC;
-- Solution 2
WITH C AS
  SELECT S.SupplierID, S.CompanyName, P.ProductID, P.UnitPrice,
    ROW_NUMBER() OVER(
      PARTITION BY P.SupplierID
      ORDER BY P.UnitPrice DESC, P.ProductID DESC) AS RowNum
  FROM dbo.Suppliers AS S
    JOIN dbo.Products AS P
      ON P.SupplierID = S.SupplierID
SELECT SupplierID, CompanyName, ProductID, UnitPrice
FROM C
WHERE RowNum <= 10
ORDER BY SupplierID, ProductID DESC, UnitPrice DESC;
Best Regards,Uri Dimant SQL Server MVP,
http://sqlblog.com/blogs/uri_dimant/
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