CREATE                PROCEDURE [dbo].[bdCustomerAllocate_sel]
@TranType varchar(40) = NULL,
@Id int = NULL,
@CustomerID int = NULL,
@OpenDate varchar(20) = NULL,       //在 AS 之前的是形参，则程序中传值，程序中传值个数可少于形参个数，前提是没有被传的形参要赋值，如NULL

AS
DECLARE @CustoemrName varchar(20)        //在As之后用 Declare定义变量,只在存储过程内部使用，不是形参。
SET @CustomerName = ''
IF(@TranType = 'personalcustomerlist')
BEGIN
    SELECT a.id, b.CustomerName, b.Address, b.Tel, 
    (SELECT TOP 1 FollowDate FROM bdFollowRecord T(nolock)
        WHERE T.AllocateID = a.ID) AS FollowDate
    FROM  bdCustomerAllocate a(NOLOCK)
    JOIN bmdCustomer b(NOLOCK)
    ON a.CustomerID = b.ID    
    WHERE a.IsValid = 1
END