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IS NULL SQL Predicate

 IS NULL is a predicate which is useful to identify the expression has NULL values. 

Let's look into an example of AdventureWorks2019 database,

SELECT [BusinessEntityID]
      ,[DepartmentID]
      ,[ShiftID]
      ,[StartDate]
      ,[EndDate]
      ,[ModifiedDate]
  FROM [AdventureWorks2019].[HumanResources].[EmployeeDepartmentHistory] 
  WHERE [EndDate] IS NULL

Above statement returns the EmployeeDepartmentHistory which has NULL EndDate value.







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