SQL Duplicates Issue SQL SERVER 2000

Question

I have two tables : Product and ProductRateDetail. The parent table is Product. I have duplicate records in the product table which need to be unique. There are entries in the ProductRateDetail table which correspond to duplicate records in the product table.

Somehow I need to update the ProductRateDetail table to match the original (older) ID from the Product table and then remove the duplicates from the product table. I would do this manually but there are 100's of records. i.e. something like

UPDATE tbl_productRateDetail SET productID = (originalID from tbl_product)

then something like

DELETE from tbl_product WHERE duplicate ID

and only delete the recently added ID data

example: (sorry can't work out this formatting thing)

tbl_Product

select * from dbo.Product where ProductCode = '10003'

ProductID    ProductTypeID    ProductDescription       ProductCode     ProductSize
365          1             BEND DOUBLE FLANGED      10003           80mmX90deg
1354            1             BEND DOUBLE FLANGED      10003           80mmX90deg

tbl_ProductRateDetail

SELECT * FROM [MSTS2].[dbo].[ProductRateDetail] WHERE ProductID in (365,1354)

ProductRateDetailID ProductRateID   ProductID   UnitRate
365                    1               365            16.87
1032                   5               365            16.87
2187                   10              365            16.87
2689                   11              365            16.87
3191                   12              365            16.87
7354                   21              1354           21.30
7917                   22              1354           21.30
8480                   23              1354           21.30
9328                   25              1354           21.30
9890                   26              1354           21.30
10452                  27              1354           21.30

Please help!

Answer 1

Hi jeff,

something like this should work :

1) update product Detail that references duplicates

UPDATE tbl_productRateDetail d
   SET productID = (SELECT MIN(p0.productID)
                      FROM tbl_product p0
                      JOIN tbl_product p1 
                            ON p1.ProductTypeID = p0.ProductTypeID
                           AND p1.ProductDescription = p0.ProductDescription
                           AND p1.ProductCode = p0.ProductCode
                           AND p1.ProductSize = p0.ProductSize
                     WHERE p1.productID = d.productId)
 WHERE productID IN (SELECT productID
                       FROM tbl_product
                      WHERE (ProductTypeID, 
                             ProductDescription, 
                             ProductCode, 
                             ProductSize) IN
                            (SELECT ProductTypeID, 
                                    ProductDescription, 
                                    ProductCode,
                                    ProductSize
                               FROM tbl_product
                              GROUP BY ProductTypeID, 
                                       ProductDescription, 
                                       ProductCode, 
                                       ProductSize
                             HAVING COUNT(*) > 1));

2) Detele duplicates

DELETE FROM tbl_product p0
 WHERE productID <> (SELECT MIN(productID)
                       FROM tbl_product p1
                      WHERE p1.ProductTypeID = p0.ProductTypeID
                        AND p1.ProductDescription = p0.ProductDescription
                        AND p1.ProductCode = p0.ProductCode
                        AND p1.ProductSize = p0.ProductSize);

Answer 2

Not tested, so syntax may have some mistakes.

First, take the minimum product id from grouped ones, and update records in ProductRateDetail

UPDATE prd1
SET prd1.ProductID = p2.ProductID
FROM ProductRateDetail prd1
INNER JOIN Product p1 ON
p1.ProductID = prd1.ProductID
INNER JOIN
(
SELECT MIN(ProductID) AS ProductID, ProductTypeID, ProductDescription, ProductCode, ProductSize
FROM Product
GROUP BY ProductTypeID, ProductDescription, ProductCode, ProductSize
) p2 ON
p1.ProductTypeID = p2.ProductTypeID AND
p1.ProductDescription = p2.ProductDescription AND
p1.ProductCode = p2.ProductCode AND
p1.ProductSize = p2.ProductSize

Then, delete the grouped products than are not the "selected" id

DELETE p1
FROM Product p1
INNER JOIN
(
SELECT MIN(ProductID) AS ProductID, ProductTypeID, ProductDescription, ProductCode, ProductSize
FROM Product
GROUP BY ProductTypeID, ProductDescription, ProductCode, ProductSize
) p2 ON
p1.ProductTypeID = p2.ProductTypeID AND
p1.ProductDescription = p2.ProductDescription AND
p1.ProductCode = p2.ProductCode AND
p1.ProductSize = p2.ProductSize AND
p1.ProductID != p2.ProductID