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sql - Replace row value with empty string if duplicate

is it possible to replace row value with empty string if duplicate value found?

For example

SELECT ProductCode, Color FROM Product

--------------------
ProductCode | Color
--------------------
   00A0B    |  Red
   00A0B    |  Blue
   00A0C    |  Red
   00A0C    |  Black
   00A0C    |  White
--------------------

to

--------------------
ProductCode | Color
--------------------
   00A0B    |  Red
            |  Blue
   00A0C    |  Red
            |  Black
            |  White
--------------------

I'm using SQL Server 2012.

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1 Answer

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Often, this type of transformation is better done at the application layer, because the result-set is not "SQL-ish". That is, the ordering is important for understanding the rows.

But, you can do this as:

select (case when row_number() over (partition by ProductCode order by (select NULL)) = 1
             then ProductCode
        end) as ProductCode
       Color
from Product
order by ProductCode;

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