存储过程计算和性能改进答案

【问题标题】：STORED PROCEDURE Calculations & performance improvements存储过程计算和性能改进
【发布时间】：2009-08-26 13:06:57
【问题描述】：

我目前有以下存储过程；

CREATE PROCEDURE web.insertNewCampaign
   (
   @tmp_Id BIGINT,
   @tmp_Title VARCHAR(100),
   @tmp_Content VARCHAR(8000),
   @tmp_Pledge DECIMAL(7,2),
   --@tmp_Recipients BIGINT,
   @tmp_Date DATETIME,
   @tmp_Private BIT,
   @tmp_Template BIGINT,
   @tmp_AddyBook BIGINT
   )
AS
   declare @recipients BIGINT
   declare @tmp_IDENTITY BIGINT
   declare @fave BIGINT
   declare @allocation VARCHAR(50)

   --insert campaign data
   BEGIN TRAN
   SELECT @recipients = addMaster_NoRecipients FROM tbl_AddressBookMaster 
   WHERE addMaster_UserId = @tmp_Id AND addMaster_Key = @tmp_AddyBook;
   INSERT INTO TBL_CAMPAIGNS ([campaign_MemberId], [campaign_Title], [campaign_Content], [campaign_Pledge], [campaign_Date], [campaign_Private], [campaign_Template], [campaign_AddressBook], [campaign_Recipients]) 
   VALUES (@tmp_Id, @tmp_Title, @tmp_Content, @tmp_Pledge, @tmp_Date, @tmp_Private, @tmp_Template, @tmp_AddyBook, @recipients)
   SELECT @tmp_IDENTITY = SCOPE_IDENTITY() --this returns the newly added IDENTITY ID
   COMMIT
......

所以我有两个问题：

1) 我如何将@tmp_Pledge 除以@recipients 以给出@allocation 例如：(@allocation = @tmp_Pledge / @recipients)

2) 是否可以将这些语句组合成更有效的语句，将@allocation 作为值有效地插入到 [campaign_RecipShare] 列中，并减少对这些声明变量的需求？

非常感谢您为任一问题提供的任何帮助。

;-)

【问题讨论】：

标签： sql sql-server sql-server-2005 tsql stored-procedures

【解决方案1】：

第一次选择后，可以这样设置@allocation：

set @allocation = @tmp_pledge / @recepients

至于让它更高效，已经相当高效了——你不会少走任何步骤，但你可以稍微压缩一下代码：

INSERT INTO TBL_CAMPAIGNS (
    [campaign_MemberId], [campaign_Title], [campaign_Content], 
    [campaign_Pledge], [campaign_Date], [campaign_Private], 
    [campaign_Template], [campaign_AddressBook], [campaign_Recipients],
    [capmain_RecipShare]) 
SELECT 
    @tmp_Id, @tmp_Title, @tmp_Content, 
    @tmp_Pledge, @tmp_Date, @tmp_Private, 
    @tmp_Template, @tmp_AddyBook, addMaster_NoRecipients,
    @tmp_Pledge / addMaster_NoReceipients as Allocation
FROM
    tbl_AddressBookMaster
WHERE
    addMaster_UserId = @tmp_Id
    AND addMaster_Key = @tmp_AddyBook

SELECT @tmp_IDENTITY = SCOPE_IDENTITY() --this returns the newly added IDENTITY ID

这也消除了您在 insert 语句之外计算 @allocation 成员的需要。

【讨论】：

看起来不错，但是 sql manager 不会编译它。它说 addMaster_NoReceipients 的第二个引用不是有效的列名。

【解决方案2】：

1) @tmp_pledge / @recepients - 我假设分配是 TBL_CAMPAIGNS 中某种形式的数字字段，在 varchar 中保存数字不是一个好主意。

2) 您只需要构建一个 select 来返回其他表中的所有值以及与要插入的列匹配的参数。

insert into TBL_CAMPAIGNS ([campaign_MemberId], [campaign_Title], [campaign_Content],    [campaign_Pledge], [campaign_Date], [campaign_Private], [campaign_Template], [campaign_AddressBook], [campaign_Recipients], [campaign_allocation) 

select @tmp_Id, @tmp_Title, @tmp_Content, @tmp_Pledge, @tmp_Date, @tmp_Private, @tmp_Template, @tmp_AddyBook, addMaster_NoRecipients, @tmp_pledge / addMaster_NoRecipients

FROM FROM tbl_AddressBookMaster 其中 addMaster_UserId = @tmp_Id AND addMaster_Key = @tmp_AddyBook;

SELECT @tmp_IDENTITY = SCOPE_IDENTITY() --返回新添加的IDENTITY ID

【讨论】：

【解决方案3】：

set @allocation = @tmp_pledge / (@recepients* 1.0)

你想这样做是因为否则你会遇到整数数学，结果将四舍五入为整数。

【讨论】：