使用 IF 语句更新行

Question

根据某些情况，我在更新结果集时遇到了困难。一些帐号为空，但基于不同的标识符进行匹配。

我正在使用匹配的帐号更新空帐号，但无法使语法完全正常工作。我遇到了错误

找不到多部分标识符“CMRR.aacount_number”

这是在我引用另一张表的几个不同的地方。

DECLARE @BatchId INT
SET @BatchId = 1030

SELECT 
    CMRR.id,
    CMRR.account_number,
    CMRR.URN
FROM 
    CRA_METRO2_REJECTED_RECORDS AS CMRR
WHERE 
    batch_id = @BatchId

IF CMRR.account_number = ''
BEGIN
    UPDATE CRA_METRO2_REJECTED_RECORDS 
    SET CMRR.account_number = (SELECT account_number 
                               FROM CRA_METRO2_REJECTED_RECORDS
                               WHERE URN = CMRR.URN
                                  AND account_number != '')
    WHERE id = CMRR.id
END

Answer 1

我相信这可以满足您的需求。我添加了 3 个变量来保存您的 select 语句中的值。您需要检查数据类型，因为我刚刚使用 INT 不知道它们在您的系统中是什么。然后在更新语句中使用这些变量。

DECLARE @BatchId INT

-- Added variables 
DECLARE @id INT
DECLARE @urn INT
DECLARE @account_number INT

SET @BatchId = 1030

-- Assign values to variables
SELECT 
    @id = id
  , @account_number = account_number
  , @urn = urn
FROM CRA_METRO2_REJECTED_RECORDS
WHERE batch_id = @BatchId


IF @account_number = ''
BEGIN
  UPDATE CRA_METRO2_REJECTED_RECORDS 
  SET account_number = (SELECT account_number 
                             FROM CRA_METRO2_REJECTED_RECORDS
                             WHERE URN = @URN
                             AND account_number != '')
  WHERE id = @id
END

编辑

经过简短的交谈，这就是解决方案。

UPDATE cmrr1
SET cmrr1.account_number = cmrr2.account_number
FROM CRA_METRO2_REJECTED_RECORDS cmrr1
JOIN CRA_METRO2_REJECTED_RECORDS  cmrr2 ON cmrr1.URN = cmrr2.URN AND cmrr2.account_number <> ''
WHERE cmrr1.batchid = @batchid
AND cmrr1.accound_number = ''