Use TVP name in SET and JOIN clauses

Question

I have a requirement in SQL Server 2008 R2 to pass in many rows for an update to many rows. I decided to try a Table Valued Parameter to accomplish this. First - I created the type on the server.

CREATE TYPE [dbo].[crm_question_idx_type] AS TABLE(
    [survey_question_id] [int] NOT NULL,
    [row_index] [int] NOT NULL,
     PRIMARY KEY (survey_question_id)
)
GO

This went fine but the problem arose when attempting to create the Stored Procedure to use the new type. The code for creating the new procedure is:

CREATE PROCEDURE dbo.crm_question_index_update
(
@question_idx dbo.crm_question_idx_type READONLY
)
AS

SET NOCOUNT ON

UPDATE crm_survey_question 
SET crm_survey_question.row_index = @question_idx.row_index
FROM crm_survey_question 
INNER JOIN @question_idx 
    ON crm_survey_question.survey_question_id =  @question_idx.survey_question_id

When I attempt to compile this on the server I get the following error:

Msg 137, Level 16, State 1, Procedure crm_question_index_update, Line 10
Must declare the scalar variable "@question_idx".

Now in my code @question_idx is an input parameter of type dbo.crm_question_idx so I can't understand why this error is popping up.

Answer 1

Aliases are your friend. In this case not only do they simplify the amount of code, but they are required when referencing table variables or TVPs.

UPDATE c
  SET c.row_index = q.row_index
  FROM dbo.crm_survey_question AS c
  INNER JOIN @question_idx AS q
  ON c.survey_question_id = q.survey_question_id;