關於跟蹤號碼..

Question

可能重複：
Get year and month from SQL

我想知道，每次我改變了一個月的跟蹤數量將在001開始..
例如，這是我的跟蹤號碼：
CAB1108072 == CAB + 11 for year, 08 for month of august, 072 running number

我是否需要在該表中爲該月份添加另一列，以便每月更改時生成跟蹤號碼？

輸出應該是這樣的。
例子：

• 2011年8月31日的流水號爲明天072是我 需要追蹤號碼開始001，因爲九月是另一個 月9月1日。

這是我的SQL：

ALTER PROCEDURE [dbo].[generateTrackNo] AS 
Declare @tempYear VARCHAR(5) 
Set @tempYear = Year(GetDate()) 
SELECT 'CAB' + SUBSTRING(CONVERT(VARCHAR(6),GETDATE(),112),3,4) + Right('0000000'+ Cast(CurrentNo as varchar(10)),3) FROM tblTrackNo where GenYear = @tempYear 
UPDATE tblTrackNo SET CurrentNo = CurrentNo + 1 where GenYear = @tempYear 

我的表tblTrackNo有兩個名，genYear Numeric(18,0)和CurrentNo Numeric(18,0)

我是否需要添加其他列一個月？

Answer 1

爲什麼使用Numeric作爲列數據類型？由於您正在構建字符串，因此我建議將它們存儲爲CHAR來保存投射：

 
genYear CHAR(2) 
CurrentNo INT 
CurrentMonth CHAR(2) 

將當前否作爲INT，以便於增加。

下面的SP（注意，我沒有測試的代碼，所以可能有一些事情你需要調整）執行以下操作：

 
1. Sets up variables to hold the 2 digit year and 2 digit month (based on the current date) as CHAR(2). 
2. Gets the record for the current year. 
3. If there is no record for the current year, it generates the tracking number and inserts a new record (for the current year) into the table 
3. If there is a record for the current year, but the month in the table is different than the current month, it generates the tracking number starting at 001. Otherwise, it generates the next tracking number. 
3A. It then updates the table. 
4. Finally, it returns the tracking number 

PROCEDURE [dbo].[generateTrackNo] AS 
BEGIN 
    DECLARE @curYear AS CHAR(2), 
      @curMonth AS CHAR(2) 

    DECLARE @dbYear AS CHAR(2), 
      @dbMonth AS CHAR(2), 
      @dbNumber AS CHAR(3), 
      @newNumber AS INT, 
      @trackingNumber AS CHAR(10) 

    -- Set up the values for the current year and current moth 
    SET @curYear = RIGHT(CAST(YEAR(GETDATE()) AS VARCHAR), 2) 
    SET @curMonth = CAST(MONTH(GETDATE()) AS VARCHAR) 
    -- Use REPLICATE to pad with a leading 0, if needed 
    SET @curMonth = REPLICATE('0', 2 - DATALENGTH(@curMonth)) + @curMonth 

    -- Get the current values from the database for the current year 
    SELECT @dbYear = genYear, 
      @dbMonth = currentMonth, 
      @dbNumber = CAST(CurrentNumber AS VARCHAR) 
    FROM tblTrackNo 
    WHERE genYear = @curYear 

    IF (@dbYear IS NOT NULL) 
     -- There was a record for the current year 
     BEGIN 
      IF (@dbMonth != @currMonth) 
       -- We're in a new month 
       BEGIN 
        SET @newNumber = 2 
        SET @trackingNumber = 'CAB' + @curYear + @curMonth + '001' 
       END 
      ELSE 
       -- We're in the current month 
       BEGIN 
        -- Pad with apprpriate number of leading 0's 
        SET @dbNumber = REPLICATE('0', 3 - DATALENGTH(@dbNumber) + @dbNumber 
        SET @trackingNumber = 'CAB' + @curYearChar + @curMonthChar + @dbNumber 
        SET @newNumber = CAST(@dbNumber AS INT) 
       END 

      -- Update the table accordingly 
      UPDATE tblTrackNo 
      SET CurrentNo = @newNumber, 
        CurrentMonth = @curMonth 
      WHERE genYear = @curYear 
     END 
    ELSE 
     -- We don't have a record in the table for the current year 
     BEGIN 
      -- Create the tracking number 
      SET @trackingNumber = 'CAB' + @curYear + @curMonth + '001' 

      -- Insert a new record into the table 
      INSERT INTO tblTrackNo(
         genYear, 
         CurrentNo, 
         CurrentMonth 
      ) 
      SELECT  @curYear, 
         2, 
         @curMonth 
     END 

    SELECT @trackingNumber AS trackingNumber 
END 

這是最有可能不最有效的SP，但它會完成這項工作。您還可能需要考慮將邏輯移出數據庫，並讓應用程序負責根據從表中返回的數據生成跟蹤編號，然後應用程序可以根據需要更新（或插入）。