如何声明多变量但只使用所需的变量？

Question

CREATE DEFINER=`NGIOne_Dev`@`%` PROCEDURE `SP_UpdateAction`(
    IN A_LoginUserID varchar(36),
    IN A_ActionID varchar(36),
    IN A_ActionCode varchar(50),
    IN A_AssignedUserID varchar(50),
    IN A_AssignedProjectID varchar(50),
    IN A_ActionStatusCode varchar(50),
    IN A_ActionEndDate varchar(50),
    IN A_LastActionComment varchar(512),
    IN T_EstimatedHrs double(10,2)
    )
BEGIN
     declare varStoryID varchar(100);
     declare varSprintName varchar(100);
    update tbl_action set 
    ActionCode= A_ActionCode, 
    AssignedUserID=A_AssignedUserID,
     AssignedProjectID=A_AssignedProjectID, 
     ActionStatusCode=A_ActionStatusCode,
     ActionEndDate=STR_TO_DATE(A_ActionEndDate,'%Y/%m/%d %H:%i'),  
     LastActionComment=A_LastActionComment,
     ModifiedOn = Now()
     where ActionID=A_ActionID;
     if(A_ActionStatusCode="Task Created")then
      select ts.StoryID,tbsp.SprintName 
      into varStoryID,varSprintName
      from tbl_sprint tbsp
      inner join  tbl_story ts  on tbsp.SprintID 
      COLLATE utf8_unicode_ci= ts.Sprint COLLATE utf8_unicode_ci
      where tbsp.Project COLLATE utf8_unicode_ci= A_AssignedProjectID
      order by tbsp.CreatedOn and ts.Title = '95 - Action item' desc limit 1;
      -- select varStoryID,varSprintName;
      set A_AssignedUserID = Concat("'",A_AssignedUserID,"'");
      -- select A_AssignedUserID;
      call SP_AddTask(A_LastActionComment,varStoryID,A_LastActionComment,A_AssignedUserID,
                    'Not started','High',varSprintName,A_AssignedProjectID,
                    '','',A_LastActionComment,A_LoginUserID,
                    T_EstimatedHrs,T_EstimatedHrs,1,0);

    end if;
END