SQL Server Stored Proc Question

Can anyone help me? I'm trying to assign @totalvisits the sum of visits.totalvisits in the example below. I keep getting errors concerning the line





"@totalvisits= Sum(visits.totalvisits) AS SumOfTotalVisits"





I can't figure out how to write it out correctly so the sum fills @totalvisits.





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DECLARE @email varchar (50)


DECLARE @totalvisits int





SELECT


@email = users.email,


@totalvisits= Sum(visits.totalvisits) AS SumOfTotalVisits


LEFT JOIN visits ON users.username = visits.username


GROUP BY users.username HAVING ((users.username) = @username)





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Any help would be appreciated!