Get Email Addresses and Send Email SQL

Let say, you have a form to order books and 'Customer' table to save the information with 'Customer Name', 'Email', 'Shipped Date', 'Received' columns.

I want to write an auto email query in SQL and would like to run by SQL agent so that the customer would get an e-mail reminder if they forget to return the books in 3 weeks from the shipped date.

Create Procedure [dbo].[AutoEmail] AS 

BEGIN 

    SET NOCOUNT ON 

            

     DECLARE @EmailList varchar(MAX)

     

     SELECT  @EmailList = COALESCE(@EmailList + ';', '') + Email

        FROM    Customer

            WHERE   (Email IS NOT NULL)

                   AND

                   (received = 0)  'bit value

                   AND

                   (ShippedDate < DATEADD(day, -21, GETDATE()))

                   

       SELECT  @EmailList

            

                

     exec msdb.dbo.sp_send_dbmail

@profile_name = 'Your Profile Name',

        @recipients='abc@hotmail.com',       

        @blind_copy_recipients = @EmailList,

        @subject = 'Books return time reminder',        

        @execute_query_database='Database Name',

        @body = 'Hello, this is a reminder email, please send us back
                           the books which you received 3 weeks ago. If you 
                           have already sent them please disregard this 
                           message.'

End