tsql - 從選擇語句更新表

Question

我有兩個表。表A和表B。
TableA包含一個varbinary（max）列 - 名爲[BinaryA] TableB包含一個包含每個varbinary卷的列（名爲「Volume」，類型爲「Long」）。

，以便選擇所有卷我查詢

SELECT ID, MyVolume = DATALENGTH([Binary]) 
FROM [VAULT].[TABLEA] 

比，我想它的體積來更新tableB的。

我接着寫

update [TableB] 
set [VOLUME] = (SELECT MyVolume = DATALENGTH([Binary]) 
       FROM [VAULT].[TABLEA] ab 
      WHERE id = ab.[Id]) 

我收到比

Cannot insert the value NULL into column 'Volume', table 'MySchema.Asset'; 
column does not allow nulls. UPDATE fails. 

雖然我沒有收到任何空當我運行

SELECT ID, MyVolume = DATALENGTH([Binary]) 
FROM [VAULT].[TABLEA] 

Answer 1

嘗試與此查詢：

UPDATE TableB 
SET TableB.[VOLUME] = DATALENGTH([T2.Binary]) 
FROM TableB 
INNER JOIN [VAULT].[TABLEA] T2 ON TableB.TAL_ID = T2.TAL_ID 

假設TableB和[VAULT]。[TABLEA]通過ID字段關聯。

Answer 2

UPDATE tableB 
SET [volume] = (SELECT RetrieveAccountNumber.AccountNumber 
          FROM RetrieveAccountNumber 
          WHERE tableB.leadid =RetrieveAccountNumber.LeadID) 
WHERE Sales_Import.leadid = (SELECT RetrieveAccountNumber.LeadID 
          FROM RetrieveAccountNumber 
          WHERE tableB.leadid = RetrieveAccountNumber.LeadID)