好久沒有寫帶CURSOR的存儲過程了，語法的有點生疏了。今天寫了個玩玩。呵呵！該功能是計算數據倉庫裏的客戶的丟失和恢複分析信息的。
/*
Definition:
Customer had sales before, but there is no sales in the last six month.
e.g:
Before or in June has sales
From July to Dec – no sales
Customer lost in Jan
*/
/*
Following is the Solution:
*/
--Create a new VSC_BI_CUSTOMER_STATUS to save the analysis data
USE [DW]
GO
/****** Object: StoredProcedure [dbo].[Setting_Customers_Status] Script Date: 2015/1/30 16:29:25 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
--Create Procedure [dbo].[Setting_Customers_Status] --創建存儲過程
ALTER Procedure [dbo].[Setting_Customers_Status] --修改存儲過程
as
--判斷表是否存在
IF NOT EXISTS (SELECT * FROM dbo.SysObjects WHERE ID = object_id(N'VSC_BI_CUSTOMER_STATUS') AND OBJECTPROPERTY(ID, 'IsTable') = 1)
BEGIN
CREATE TABLE [dbo].[VSC_BI_CUSTOMER_STATUS](
--[CUSTOMER_NAME] [nvarchar](100) Collate Chinese_PRC_CI_AS NOT NULL,
[CUSTOMER_NAME] [nvarchar](100) NOT NULL,
[CUSTOMER_ID] [int] NOT NULL,
[YEAR] [nvarchar](4) NOT NULL,
[MONTH] [nvarchar](2) NOT NULL,
[STATUS] [nvarchar](20) NOT NULL,
[INVOICE_DATE] [date] NOT NULL,
[LOST] [int] NOT NULL,
[NORMAL] [int] NOT NULL,
[NEW] [int] NOT NULL,
[RECOVER] [int] NOT NULL
) ON [PRIMARY]
ALTER TABLE [dbo].[VSC_BI_CUSTOMER_STATUS] ADD CONSTRAINT [DF_VSC_BI_CUSTOMERR_STATUS_YEAR] DEFAULT ('') FOR [YEAR]
ALTER TABLE [dbo].[VSC_BI_CUSTOMER_STATUS] ADD CONSTRAINT [DF_VSC_BI_CUSTOMER_STATUS_MONTH] DEFAULT ('') FOR [MONTH]
ALTER TABLE [dbo].[VSC_BI_CUSTOMER_STATUS] ADD CONSTRAINT [DF_VSC_BI_CUSTOMER_STATUS_LOST] DEFAULT ((0)) FOR [LOST]
ALTER TABLE [dbo].[VSC_BI_CUSTOMER_STATUS] ADD CONSTRAINT [DF_VSC_BI_CUSTOMER_STATUS_NORMAL] DEFAULT ((0)) FOR [NORMAL]
ALTER TABLE [dbo].[VSC_BI_CUSTOMER_STATUS] ADD CONSTRAINT [DF_VSC_BI_CUSTOMER_STATUS_NEW] DEFAULT ((0)) FOR [NEW]
ALTER TABLE [dbo].[VSC_BI_CUSTOMER_STATUS] ADD CONSTRAINT [DF_VSC_BI_CUSTOMER_STATUS_RECOVER] DEFAULT ((0)) FOR [RECOVER]
END
--Use the Cursor to get the target data
--測試的時候需要把表裏的數據刪除了
truncate table VSC_BI_CUSTOMER_STATUS
declare @CUSTOMER_ID int
declare @CUSTOMER_NAME nvarchar(100) --定要定義成NVARCHAR的類型，否則後面有漢字的時候，有可能會出現亂碼
declare @INVOICE_DATE date
--記錄遊標裏的下一條記錄
declare @CUSTOMER_ID_NEXT int
declare @CUSTOMER_NAME_NEXT nvarchar(100) --定要定義成NVARCHAR的類型，否則後面有漢字的時候，有可能會出現亂碼
declare @INVOICE_DATE_NEXT date
--記錄丟失客戶的那個的月份
declare @INVOICE_DATE_LOST date
--記錄循環次數
declare @LOOP_COUNT INT
SET @LOOP_COUNT=0
declare @sql char(5000)
declare table_customer_cursor cursor for
select c.[CUSTOMER_ID],c.CUSTOMER_NAME,h.[INVOICE_DATE]
--COUNT(*) TransTimes
from [dbo].[VSC_BI_CUSTOMER] c,[dbo].[VSC_BI_INV_HEADERS] h
where c.[CUSTOMER_ID]=h.[CUSTOMER_ID] and h.[INVOICE_DATE]>'2012-03-31'
group by c.[CUSTOMER_ID],c.CUSTOMER_NAME,h.[INVOICE_DATE]
--having count(*)>=1
order by c.[CUSTOMER_ID],c.CUSTOMER_NAME,h.[INVOICE_DATE]
open table_customer_cursor
fetch next from table_customer_cursor into @CUSTOMER_ID,@CUSTOMER_NAME,@INVOICE_DATE
WHILE @@FETCH_STATUS = 0
BEGIN
--第一進入循環的時候，@CUSTOMER_ID_NEXT是空的，這個時候直接用上面這個語句取到的值fetch next from table_customer_cursor into @CUSTOMER_ID,@CUSTOMER_NAME,@INVOICE_DATE
if @CUSTOMER_ID_NEXT<>''
BEGIN
set @CUSTOMER_ID=@CUSTOMER_ID_NEXT
set @CUSTOMER_NAME = @CUSTOMER_NAME_NEXT
set @INVOICE_DATE = @INVOICE_DATE_NEXT
END
SET @LOOP_COUNT=@LOOP_COUNT+1
print @LOOP_COUNT
--第一條記錄插入到[dbo].[CUSTOMER_STATUS]表裏，而且STATUS=NEW
IF @LOOP_COUNT=1
BEGIN
--set @sql='insert into CUSTOMER_STATUS(CUSTOMER_ID,CUSTOMER_NAME,STATUS,INVOICE_DATE) values('+@CUSTOMER_ID+','+''''+@CUSTOMER_NAME+''''+','+'NEW'+','+@INVOICE_DATE+')'
--print @sql
--exec(@sql)
insert into VSC_BI_CUSTOMER_STATUS(CUSTOMER_ID,CUSTOMER_NAME,STATUS,INVOICE_DATE)values(+@CUSTOMER_ID,@CUSTOMER_NAME,'NEW',@INVOICE_DATE)
END
ELSE --不是一個客戶的第一條記錄
--set @sql='delete from '+@tblname
--exec(@sql)
print @CUSTOMER_ID
print @CUSTOMER_NAME
print @INVOICE_DATE
fetch next from table_customer_cursor into @CUSTOMER_ID_NEXT,@CUSTOMER_NAME_NEXT,@INVOICE_DATE_NEXT
--set @CUSTOMER_ID_NEXT = @CUSTOMER_ID
--set @CUSTOMER_NAME_NEXT = @CUSTOMER_NAME
--set @INVOICE_DATE_NEXT = @INVOICE_DATE
--由於HK的服務器數據庫的編碼方式導致了漢字顯示亂碼，所以用一個N'標識，表示加N前綴指定後面的字符串爲UNICODE常量，
print N'顯示下一行的記錄'
print @CUSTOMER_ID_NEXT
print @CUSTOMER_NAME_NEXT
print @INVOICE_DATE_NEXT
--計算邏輯如下：
--如果相鄰的兩條記錄是一個相同的客戶，則需要比較兩條記錄的時間間隔，
--1，如果時間間隔大於6個月，則表示這個客戶在上一個時間的基礎上加6個月份丟失的，這個時候需要把該客戶在那個丟失的月份插入到CUSTOMER_STATUS表裏
--同時還要把此期間的下區間記錄插入到CUSTOMER_STATUS表，表示此客戶在此條記錄的月份RECOVERY
--2, 如果時間間隔小於6個月在插入此記錄到CUSTOMER_STATUS表裏，同時STATUS是NORMAL
--總上所述，除了需要把循環的表記錄都要插入CUSTOMER_STATUS表裏外，還要插入丟失的那個月份的信息
--如果一個客戶循環到最後一條記錄，此時要判斷該記錄距離getdate的時間是否大於6個月，如果是則是丟失LOST(這個時候需要再插入一條丟失的記錄，
--即最後一次交易的時間加6個月)，否則是正常NORMAL
--Notes:如果客戶只有一次交易，則需要特別的考慮，這個時候需要插入兩條記錄，一條是NEW，一條是丟失的記錄
IF (@CUSTOMER_ID=@CUSTOMER_ID_NEXT and @CUSTOMER_NAME=@CUSTOMER_NAME_NEXT) --表示還是同一個客戶
--BEGIN
--@INVOICE_DATE_NEXT-@INVOICE_DATE>180
if DATEDIFF(day,@INVOICE_DATE,@INVOICE_DATE_NEXT)>180
begin
--set @INVOICE_DATE_LOST=@INVOICE_DATE+180
set @INVOICE_DATE_LOST=dateadd(day,180,@INVOICE_DATE)
--插入客戶丟失的月份信息
insert into VSC_BI_CUSTOMER_STATUS(CUSTOMER_ID,CUSTOMER_NAME,STATUS,INVOICE_DATE)values(+@CUSTOMER_ID_NEXT,@CUSTOMER_NAME_NEXT,'LOST',@INVOICE_DATE_LOST)
--插入恢復的月份信息
insert into VSC_BI_CUSTOMER_STATUS(CUSTOMER_ID,CUSTOMER_NAME,STATUS,INVOICE_DATE)values(+@CUSTOMER_ID_NEXT,@CUSTOMER_NAME_NEXT,'RECOVER',@INVOICE_DATE_NEXT)
end
else
insert into VSC_BI_CUSTOMER_STATUS(CUSTOMER_ID,CUSTOMER_NAME,STATUS,INVOICE_DATE)values(+@CUSTOMER_ID_NEXT,@CUSTOMER_NAME_NEXT,'NORMAL',@INVOICE_DATE_NEXT)
ELSE --不是同一個客戶
BEGIN
SET @LOOP_COUNT=0 --是爲了把每個客戶的第一次交易時，他們會是我們的新客
--此時客戶循環到最後一條記錄，此時要判斷該記錄距離getdate的時間是否大於6個月，如果是則是丟失LOST(這個時候需要再插入一條丟失的記錄，
--即最後一次交易的時間加6個月)，否則是正常NORMAL
if DATEDIFF(day,@INVOICE_DATE,getdate())>180
BEGIN
insert into VSC_BI_CUSTOMER_STATUS(CUSTOMER_ID,CUSTOMER_NAME,STATUS,INVOICE_DATE)values(+@CUSTOMER_ID,@CUSTOMER_NAME,'LOST',dateadd(day,180,@INVOICE_DATE))
--update CUSTOMER_STATUS set STATUS='LOST' where CUSTOMER_ID=@CUSTOMER_ID andCUSTOMER_NAME=@CUSTOMER_NAME
and INVOICE_DATE=dateadd(day,180,@INVOICE_DATE)
END
END
END
close table_customer_cursor
deallocate table_customer_cursor
--更新下YEAR和MONTH,其實BI裏可以直接用INOVICE_DATE就可以關聯到YEAR，MONTH，QUARTER您自己看吧，需要就加上。
update VSC_BI_CUSTOMER_STATUS set YEAR=YEAR(INVOICE_DATE),MONTH=MONTH(INVOICE_DATE)
--更新LOST，RECOVER，NEW，NORMAL數量
update VSC_BI_CUSTOMER_STATUS set LOST=1 WHERE STATUS='LOST'
update VSC_BI_CUSTOMER_STATUS set RECOVER=1 WHERE STATUS='RECOVER'
update VSC_BI_CUSTOMER_STATUS set NEW=1 WHERE STATUS='NEW'
update VSC_BI_CUSTOMER_STATUS set NORMAL=1 WHERE STATUS='NORMAL'
/*調用執行Procedure
--EXEC [dbo].[Setting_Customers_Status]
*/
/* 驗證用的SQL
truncate table CUSTOMER_STATUS
select * from CUSTOMER_STATUS
where 1=1
--AND status='RECOVERY'
AND CUSTOMER_ID=3698
order by customEr_id ,invoice_date
SELECT * FROM [dbo].[VSC_BI_CUSTOMER_STATUS] where CUSTOMER_ID=3698
SELECT * FROM [dbo].[VSC_BI_CUSTOMER_STATUS] where STATUS='RECOVER'
TRUNCATE TABLE [dbo].[VSC_BI_CUSTOMER_STATUS]
--漢字亂碼
select * from [dbo].[VSC_BI_CUSTOMER_STATUS] WHERE CUSTOMER_ID=12101
select * from [dbo].[VSC_BI_CUSTOMER_STATUS] WHERE CUSTOMER_ID=49531
*/
在寫上面的存儲過程的時候出現了下面的小故事需要修改:
1，一開始我在創建表的時候，其中一個CUSTOMER_NAME的列我用的是char(100), 由於我們DW服務器的數據庫字符集是：Chinese_HongKong_Stroke_90_CI_AS,這個導致我的漢字部分有出現問號亂碼的情況出現。
2，直到上面的原因後，我把表的相關子段設計成NVARCHAR類型，但是在執行存儲過程後還是發現和上面一樣有問號亂碼
3，再次查看存儲過程，發現我存儲過程的@CUSTOMRR_NAME的類型些的是char(100)，把類型改成nvarchar(100)後，再次執行存儲過程，終於沒有了亂碼。
Lessons Learned:
如果數據庫的數據只是英文和數字，可以用varchar類型，如果數據庫需要程序很多國家的語言，尤其像漢字的話，就必須把字段類型設計成nvarchar.
其中N表示是National Language，國家語言。NVARCHAR表示用2個字節存儲一個字符，不管是英文字母還是漢字等。
