SQL更新1个表中的多行

Question

I have a question. I am using MS SQL Server Management Studio by the way.

I have a Dictionary table with a lot of translations. I need to copy a complete description from a languageID to another languageID.

Example below.

LanguageID | Description
    2      | Some text
    2      | More text
    2      | Some more text
   10      | *needs to be replaced
   10      | *needs to be replaced
   10      | *needs to be replaced

The result must be like this:

LanguageID | Description
    2      | Some text
    2      | More text
    2      | Some more text
   10      | Some text
   10      | More text
   10      | Some more text

The description of LanguageID 2 and 10 must be exactly the same.

My current Query runs into an error:

update tblDictionary
set Description = (Select Description from tblDictionary where 
tblDictionary.LanguageID = 2)
where LanguageID = 10

Msg 512, Level 16, State 1, Line 1 Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= ,

, >= or when the subquery is used as an expression. The statement has been terminated.

Answer 1

If all translations for LanguageID 10 must be exact the same as for languageID 2 then its easier to delete all translations for ID 10 and then insert them back again.
Something like this

delete from tblDictionary where LanguageID = 10;

insert into tblDictionary (LanguageID, Description)
select 10, d.Description
from   tblDictionary d
where  d.LanguageID = 2

This method also has the advantage that if there are less records with LanguageID = 10 then there are for LanguageID = 2 this will be corrected in the same process.

If you have more columns in tblDictionary than you will need to modify the insert statement off course

Answer 2

DECLARE @temp varchar(50)
DECLARE language_cursor CURSOR FOR  
SELECT Description FROM tblDictionary  
WHERE LanguageID = 2  
ORDER BY Description;  

OPEN language_cursor;  

-- Perform the first fetch.  
FETCH NEXT FROM language_cursor
into @temp;  

-- Check @@FETCH_STATUS to see if there are any more rows to fetch.  
WHILE @@FETCH_STATUS = 0  
BEGIN  
   update TOP (1) tblDictionary
   set Description = @temp
   where Description = ''
   and LanguageID = 10;  
   FETCH NEXT FROM language_cursor
   into @temp;
END  

CLOSE language_cursor;  
DEALLOCATE language_cursor;  

Set all languageID 10 to empty first, then loop all description from languageID 2 to update into languageID 10 one by one until all empty description from languageID10 is filled.

Answer 3

Now if you really want an update, something like this should work, even though I think the structure of the table needs to be improved.

WITH l2 AS 
(SELECT *,  
 ROW_NUMBER() OVER(PARTITION BY LanguageId ORDER BY Description ASC) AS No FROM tblDictionary WHERE LanguageId=2),
l10 AS 
(SELECT *,  
 ROW_NUMBER() OVER(PARTITION BY LanguageId ORDER BY Description ASC) AS No FROM tblDictionary WHERE LanguageId=10)

UPDATE l10 SET Description = l2.Description 
FROM l10
INNER JOIN l2 ON l10.No = l2.No