SQL query to show all records if the parameter is NULL

Sometimes we have to use a parameter that will form the basis of the condition in the Query. For e.g. if the parameter has a value, then we want to use it in the condition, otherwise we want to retrieve all the records. This can be achieved by:

declare @vEname nvarchar(60)
set @vEname = null
Select * from Emp where Ename = isnull(@vEname,Ename)

In the above script, if @vEname has some value, then the query will run based on that condition, otherwise it will run on the condition of "Ename = Ename" column, which will always return true and hence will return all the records.

Happy Coding.!

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Rohit Dhand

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