multi part indentifier could not be bound? - sql

Question

I'm trying to use two tables in a stored procedure but am getting this error on the final line
''multi part identifier T.HireDate could not be bound''
I'm guessing its to do with the joining of the tables but am a little lost. Heres my code:
CREATE PROC spPayIncreaseCheck
AS
SELECT T.ID,FName,LName,HireDate,Payrate
FROM Assignment.dbo.Payments pay
join Assignment.dbo.Teachers T
ON pay.ID = T.ID
UPDATE Assignment.dbo.Payments
SET Payrate = 'High'
where T.HireDate < dateadd(year, -3, GETDATE())

Answer 1

Are you trying to update, or are you trying to select?
That is the wrong form for an update using a join in sql server.
The correct form would be like so:
update pay
set Payrate = 'High'
from Assignment.dbo.Payments pay
inner join Assignment.dbo.Teachers T
on pay.ID = T.ID
where T.HireDate < dateadd(year, -3, getdate());
Also, are you sure on pay.ID = T.ID is the correct join clause? Normally you would expect to see something like on pay.TeacherID = T.ID instead.

Answer 2

You are updating the Assignment.dbo.Payments table and in the WHERE condition you have a t.HireDate but t is not an alias that is used in the UPDATE statement.
In UPDATE you cannot use aliases.
Also, please notice that the SELECT and UPDATE statements are completely non-related inside your stored procedure. It is not clear though if you need them to be related.
You need an UPDATE FROM to do a set-based update:
UPDATE Assignment.dbo.Payments
SET Payrate = 'High'
FROM
SELECT T.ID,FName,LName,HireDate,Payrate
FROM Assignment.dbo.Payments pay
JOIN Assignment.dbo.Teachers T ON pay.ID = T.ID
WHERE T.HireDate < DATEADD(YEAR, -3, GETDATE())

Answer 3

The simplest way to achieve this, is using an exists clause to check if the payment record matches the teacher record:
update Assignment.dbo.Payments
set Payrate = 'High'
where exists ( select 1
from Assignment.dbo.Teachers
where Payments.ID = Teachers.ID
and Teachers.HireDate < dateadd(year, -3, getdate()) )