Difference between Row Number, Rank and Dense Rank | SQL Interview Question | IQBees

Опубликовано: 25 Май 2021
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Hi Friends,

Difference between row_number(), rank() and dense_rank() window functions in SQL

Though all three are ranking functions in SQL, also known as a window function in Microsoft SQL Server, the difference between rank(), dense_rank(), and row_number() comes when you have ties on ranking i.e. duplicate records. For example, if you are ranking employees by their salaries then what would be the rank of two employees of the same salaries? It depends on which ranking function you are using like row_number, rank, or dense_rank.

The row_number() function always generates a unique ranking even with duplicate records i.e. if the ORDER BY clause cannot distinguish between two rows, it will still give them different.

The Rank() and Dense_Rank() will give the same rame for same value. Dense_Rank() values are not skipped in the event of ties. Rows with equal values for the ranking criteria receive the same rank whereas RANK() will leave gaps after two or more rows with the same rank.

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IQBees
#Rank #DENSERANK #ROWNUMBER #SQLRANKINGFUNCTION

Difference between row_number(), rank() and dense_rank()
Difference between rownumber, rank and dense rank