DF048: A procedure parameter or variable is declared but never used.

The topic describes the DF048 T-SQL code analysis rule.

Message

A procedure parameter or variable is declared but never used.

Description

Avoiding unused parameters and variables is important to maintain code clarity, optimize performance, facilitate maintainability, and reduce unnecessary resource consumption.

Noncompliant code example

CREATE PROCEDURE dbo.ProcDemo (
  @LocationId SMALLINT,
  @LocationName NVARCHAR(255)
)
AS
BEGIN
  SET NOCOUNT ON;
 
  SELECT L.LocationID, L.Name
  FROM Production.Location l;
 
  DECLARE @location_count SMALLINT;
  SET @location_count = (
    SELECT COUNT(*) AS count_row
    FROM Production.Location l
  );
END;
GO

Compliant solution

CREATE PROCEDURE dbo.ProcDemo (
  @LocationId SMALLINT,
  @LocationName NVARCHAR(255) OUTPUT
)
AS
BEGIN
  SET NOCOUNT ON;
  DECLARE @LocName NVARCHAR(255);
 
  SET @LocName = (
    SELECT l.Name
    FROM Production.Location l
    WHERE l.LocationID = @LocationId
    ORDER BY l.Name
      OFFSET 0 ROWS
      FETCH NEXT 1 ROWS ONLY
  );
 
  SET @LocationName = @LocName;
  RETURN @LocationName;
END;
GO