推荐的存储过程编写方法是什么？

我通常使用以下方式编写存储过程：

ALTER PROCEDURE MasterInsertUpdateDelete  
    (@id INTEGER,  
     @first_name VARCHAR(10),  
     @last_name VARCHAR(10),  
     @salary DECIMAL(10,2),  
     @city VARCHAR(20),  
     @StatementType NVARCHAR(20) = '')  
AS  
BEGIN  
    IF @StatementType = 'Insert'  
    BEGIN  
        INSERT INTO employee (id, first_name, last_name, salary, city) 
        VALUES (@id, @first_name, @last_name, @salary, @city)  
    END  

    IF @StatementType = 'Select'  
    BEGIN  
        SELECT * FROM employee  
    END  

    IF @StatementType = 'Update'  
    BEGIN  
        UPDATE employee 
        SET First_name = @first_name, 
            Last_name = @last_name, 
            salary = @salary,  
            city = @city  
        WHERE id = @id  
    END  
    ELSE IF @StatementType = 'Delete'  
    BEGIN  
        DELETE FROM employee 
        WHERE id = @id  
    END  
END

第二种方法是将一个存储过程分为4个单独的存储过程，以用于插入，删除，选择和更新表。

关于性能，推荐哪一个？