Question

i have a stored procedure that has to retrieve data from multiple tables

something like

SELECT [AppointmentId]
  ,[ContactId]
  ,[Date]
  ,[BookedBy]
  ,[Details]
  ,[Status]
  ,[Time]
  ,[Type]
  ,[JobId]
  ,[AppointmentFor]
  ,(Select PersonFirstName from Person where Person_Id = [AppointmentFor]) As UserFirstName
  ,(Select PersonLastName from Person where Person_Id = [AppointmentFor]) As UserLastName

  ,(Select PersonFirstName from Person where Person_Id = [ContactId]) As ContactFirstName      
  ,(Select PersonLastName from Person where Person_Id = [ContactId]) As ContactLastName           

 FROM [dbo].[Appointments]

my question is
there is any other more efficient way to do this? Or is this the right approach?

I am working on a Sql server 2008
Thanks

Answer 1

If i understand correctly you will need to use two joins, so that you can match on [AppointmentFor] and [ContactId].

I have also aliased the table, which is a good habit to get into when joined across mutiple tables.

SELECT a.[AppointmentId] 
  ,a.[ContactId] 
  ,a.[Date] 
  ,a.[BookedBy] 
  ,a.[Details] 
  ,a.[Status] 
  ,a.[Time] 
  ,a.[Type] 
  ,a.[JobId] 
  ,a.[AppointmentFor] 
  ,p1.PersonFirstName As UserFirstName 
  ,p1.PersonLastName As UserLastName 
  ,p2.PersonFirstName As ContactFirstName       
  ,p2.PersonLastName  As ContactLastName            

 FROM [dbo].[Appointments] a

    INNER JOIN Person p1 ON p1.Person_Id = a.[AppointmentFor]

    INNER JOIN Person p2 ON p2.Person_Id = a.[ContactId]