SQL Server tutorial for beginners - Difference between rows and range

range vs rows in sql server difference between rows clause and range clause in sql server range clause vs rows clause in sql server sql server running total query running total example in sql server In this video we will discuss the difference between rows and range in SQL Server. This is continuation to Part 116. Please watch Part 116 from SQL Server tutorial before proceeding. Healthy diet is very important both for the body and mind. If you like Aarvi Kitchen recipes, please support by sharing, subscribing and liking our YouTube channel. Hope you can help. https://www.youtube.com/channel/UC7sEwIXM_YfAMyonQCrGfWA/?sub_confirmation=1 Let us understand the difference with an example. We will use the following Employees table in this demo. SQL Script to create the Employees table Create Table Employees ( Id int primary key, Name nvarchar(50), Salary int ) Go Insert Into Employees Values (1, 'Mark', 1000) Insert Into Employees Values (2, 'John', 2000) Insert Into Employees Values (3, 'Pam', 3000) Insert Into Employees Values (4, 'Sara', 4000) Insert Into Employees Values (5, 'Todd', 5000) Go Calculate the running total of Salary and display it against every employee row The following query calculates the running total. We have not specified an explicit value for ROWS or RANGE clause. SELECT Name, Salary, SUM(Salary) OVER(ORDER BY Salary) AS RunningTotal FROM Employees So the above query is using the default value which is RANGE BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW This means the above query can be re-written using an explicit value for ROWS or RANGE clause as shown below. SELECT Name, Salary, SUM(Salary) OVER(ORDER BY Salary RANGE BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) AS RunningTotal FROM Employees We can also achieve the same result, by replacing RANGE with ROWS SELECT Name, Salary, SUM(Salary) OVER(ORDER BY Salary ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) AS RunningTotal FROM Employees What is the difference between ROWS and RANGE To understand the difference we need some duplicate values for the Salary column in the Employees table. Execute the following UPDATE script to introduce duplicate values in the Salary column Update Employees set Salary = 1000 where Id = 2 Update Employees set Salary = 3000 where Id = 4 Go Now execute the following query. Notice that we get the running total as expected. SELECT Name, Salary, SUM(Salary) OVER(ORDER BY Salary ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) AS RunningTotal FROM Employees The following query uses RANGE instead of ROWS SELECT Name, Salary, SUM(Salary) OVER(ORDER BY Salary RANGE BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) AS RunningTotal FROM Employees Notice we don't get the running total as expected. So, the main difference between ROWS and RANGE is in the way duplicate rows are treated. ROWS treat duplicates as distinct values, where as RANGE treats them as a single entity. All together side by side. The following query shows how running total changes 1. When no value is specified for ROWS or RANGE clause 2. When RANGE clause is used explicitly with it's default value 3. When ROWS clause is used instead of RANGE clause SELECT Name, Salary, SUM(Salary) OVER(ORDER BY Salary) AS [Default], SUM(Salary) OVER(ORDER BY Salary RANGE BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) AS [Range], SUM(Salary) OVER(ORDER BY Salary ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) AS [Rows] FROM Employees Text version of the video http://csharp-video-tutorials.blogspot.com/2015/10/difference-between-rows-and-range.html Slides http://csharp-video-tutorials.blogspot.com/2015/10/difference-between-rows-and-range_8.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists