The second value with the result 2 is clearly the duplicate value, which I have inserted accidently (or whatever reason).įair enough. The OutputĪs you can see, the method has returned two rows for Employee MIKE PEARL i.e. The PARTITION BY option is optional, you may or may not use it, but in this scenario, we need it. If a table has unique set of rows, then ROW_NUMBER() will assign each row a value of 1.Ĭreate a table and add a few rows, particularly a set of duplicate rows. SQL server ROW_NUMBER() returns the total count (in numbers) of a row. There are many ways to achieve this, but I found a simple method called the ROW_NUMBER().Īlso Read: Learn about SQL Server LEFT() and RIGHT() functions ROW_NUMBER() The first step is to trace the duplicate records or rows in a table. The best way to design a database is to draw diagrams that will give you a clear picture of the entire database structure.Īnyways, we have found duplicate rows in our tables and we need to eliminate them. It is the job of a DBA to ensure that the database and its objects are designed with utmost care. Technically, a table must not, in anyway, accept duplicate set of records in the first place. The matter gets worse when company auditors complain about irregularities in the balance sheet etc. Duplicate rows in tables can be very annoying for DBA’s and programmers, as it raises many uncomfortable questions about the authenticity of data in a database.
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