How to change the Row Number behavior in my T-SQL Query? - sql

Question

I am using SQL Server 2014 and I have the following T-SQL query running against a table (tbl1).
Extract of tbl1:
emp_code Name Address Company
---------------------------------------
100 Peter London ABC
125 Allan Cambridge DCE
125 Allan Cambridge DCE
115 John Suffolk ABC
115 John Suffolk XYZ
154 Mary Highlands ABC
154 Mary Bristol ABC
124 Mary Chester ABC
My T-SQL query stands as follows:
SELECT
[ID],
[Name],
[Address],
[Company],
ROW_NUMBER() OVER (PARTITION BY [emp_code] ORDER BY [Address]) AS RowNumber
FROM
[tbl1]
Output from above query:
emp_code Name Address Company RowNumber
--------------------------------------------------------
100 Peter London ABC 1
125 Allan Cambridge DCE 1
125 Allan Cambridge DCE 2
115 John Suffolk ABC 1
115 John Suffolk XYZ 2
154 Mary Highlands ABC 1
154 Mary Bristol ABC 2
154 Mary Chester ABC 3
Output I'm after:
emp_code Name Address Company RowNumber
---------------------------------------------------------
100 Peter London ABC 1
125 Allan Cambridge DCE 1
125 Allan Cambridge DCE 1
115 John Suffolk ABC 1
115 John Suffolk XYZ 1
154 Mary Highlands ABC 1
154 Mary Bristol ABC 2
154 Mary Chester ABC 3
I want my RowNumber (or change the column name if need be) to change based on the [Address] column for each [emp_code]. If the employee has the SAME address, it should have the same value (that is, 1). Else, it should give the values as in the case of employee "Mary" (above output).
I am assuming the Row_Number() function is not the right one to be used for what I'm after.
Any help would be appreciated.

Answer 1

I think you want DENSE_RANK here rather than ROW_NUMBER():
SELECT [ID], [Name], [Address], [Company],
DENSE_RANK() OVER (PARTITION BY [emp_code]
ORDER BY [Address]) AS DenseRank
FROM [tbl1];
Demo