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SQL Tutorial - Working with Variables

Another video brought to you by BeardedDev, bringing you tutorials on Business Intelligence, SQL Programming and Data Analysis. You can now support me on patreon -   / beardeddev   In this SQL Tutorial we take a look at how to work with variables in SQL Server. Understanding variables and how they can be used is an important skill in any developers armoury. Variables open us up to a new world of opportunities when working with data and can be used for looping or controlling conditional logic. In this video we look at a simple query that we are asked to run over and over, we talk about how we can use variables to make the query more dynamic and less prone to errors. The SQL used in this video: DECLARE @StartDate DATE, @EndDate DATE SET @StartDate = '20180210' SET @EndDate = '20180220' SELECT Sales_Customer_Id , SUM(Sales_Amount) AS Spend FROM dbo.Sales WHERE Sales_Date (greater than)= @StartDate AND Sales_Date (less than)= @EndDate GROUP BY Sales_Customer_Id