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Index scan and index seek in sql server
Software requirement
Technical knowledge
Scan and seek
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Types of scan and seek in SQL server
Table Scan
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SELECT [PersonId],[PersonName],[Address] FROM [Test].[dbo].[Person]
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Clustered index scan and seek
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SELECT [PersonId] ,[PersonName] ,[Address] FROM [Test].[dbo].[Person] where Personid =1
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How isnull functions change the behavior?
select [Address] from Person where [Address] = 'Address 1'
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select [Address] from Person where Isnull([Address],'') = 'Address 1'
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