I wish you all a good afternoon. It is difficult to decide on the correct answer... 🙂

https://technet.microsoft.com/en-us/library/ms179300(v=sql.105).aspx

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USE AdventureWorks2014;-- or AdventureWorks2008R2;

GO

SELECT TOP 10 BusinessEntityID [Employee Identification Number]

FROM HumanResources.Employee;

SELECT TOP 10 BusinessEntityID 'Employee Identification Number'

FROM HumanResources.Employee;

SELECT TOP 10 BusinessEntityID "Employee Identification Number"

FROM HumanResources.Employee;

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SELECT TOP 10 BusinessEntityID AS [Employee Identification Number]

FROM HumanResources.Employee;

SELECT TOP 10 BusinessEntityID AS 'Employee Identification Number'

FROM HumanResources.Employee;

SELECT TOP 10 BusinessEntityID AS "Employee Identification Number"

FROM HumanResources.Employee;

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SELECT TOP 10 [Employee Identification Number] = BusinessEntityID, NationalIDNumber as NatId

FROM HumanResources.Employee;

SELECT TOP 10 'Employee Identification Number' = BusinessEntityID, NationalIDNumber as NatId

FROM HumanResources.Employee;

SELECT TOP 10 "Employee Identification Number" = BusinessEntityID, NationalIDNumber as NatId

FROM HumanResources.Employee;

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SELECT TOP 10 SalesOrderID, ShipDate,

DaysSinceShipped = DATEDIFF(dd, ShipDate, GETDATE() )

FROM Sales.SalesOrderHeader

WHERE ShipDate IS NOT NULL

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