1

我的车号有两部分

3 位是序列号，后 8 位是发票的月份和年份

例如：001072013

所以如果我想要下一个InvoiceNo

我像这样从数据库中最后输入的发票号码中选择

select TOP 1 InvoiceNo 
from BuyInvoice

将前 3 位数字剪掉，然后递增，并结合到发票的月份和年份

所以它会是002072013

问题是上面的语句没有返回最后一个条目值

上升和下降都不起作用

4

4 回答 4

2

我会尝试：

select TOP 1 InvoiceNo 
from BuyInvoice order by right(InvoiceNo,4) desc,
  right(InvoiceNo, 6) desc, 
  InvoiceNo desc
于 2013-07-19T12:25:36.017 回答
0

尝试

select top 1 InvoiceNo from BuyInvoice order by left(InvoiceNo,3) desc
于 2013-07-19T14:47:18.950 回答
0

我假设该BuyInvoice表有一列与列的部分InvoiceDate具有相同的值。dateInvoiceNo在这种情况下，我会使用（未测试解决方案）：

DECLARE @InvoiceDate DATE;
SET @InvoiceDate='2013-07-20';

BEGIN TRANSACTION;

DECLARE @LastInvoiceNo VARCHAR(9);

SELECT TOP(1) @LastInvoiceNo=bi.InvoiceNo 
-- This table hint (UPDLOCK) take a U lock on this row[s] so any concurrent [similar] transactions will have to wait till this transaction is finished
-- This will prevent duplicated new InvoiceNo 
FROM dbo.BuyInvoice bi WITH(UPDLOCK) 
WHERE bi.InvoiceDate=@InvoiceDate
ORDER BY bi.InvoiceNo DESC;

DECLARE @Seq SMALLINT;
SET @Seq=ISNULL(CONVERT(SMALLINT,LEFT(@LastInvoiceNo,3)),0);
SET @Seq=@Seq+1;

DECLARE @NewInvoiceNo VARCHAR(9);
SET @NewInvoiceNo=RIGHT('00'+CONVERT(VARCHAR(3),@Seq),3)+STUFF(STUFF(CONVERT(VARCHAR(10),@InvoiceDate,101),3,1,''),5,1,''); -- Convert style 101 = mm/dd/yyyy

...

INSERT dbo.BuyInvoice(InvoiceNo,InvoiceDate,...)
VALUES (@NewInvoiceNo,@InvoiceDate,...);
...

COMMIT TRANSACTION;

另外，如果需要，我会BEGIN TRY ... END CATCH用来拦截异常并回滚此事务（链接：示例 B）。

此外，我将创建以下索引：

-- This way, the InvoiceNo column will have uniques values
CREATE UNIQUE INDEX IUN_BuyInvoice_InvoiceNo
ON dbo.BuyInvoice(InvoiceNo);
GO
-- This index is used by SELECT TOP(1) ... query
CREATE UNIQUE INDEX IN_BuyInvoice_InvoiceDate_InvoiceNo
ON dbo.BuyInvoice(InvoiceDate,InvoiceNo);
GO
于 2013-07-19T12:56:09.163 回答
0

尝试这个

select TOP 1 InvoiceNo 
  from BuyInvoice order by InvoiceNo desc
于 2013-07-19T12:16:25.240 回答