Question

I have a table Items which should have a corresponding record in the table LanguageText. The ID (Identity) of LanguageText is registered in the Items.LanguageTextId field in my Items table.

What I want to accomplish is a merge between LanguageText and Items for all records with null in Items.LanguageTextId and insert the itemname / text of these Item records in LanguageText plus update the LanguageTextId with the ID value from the newly inserted LanguageText record (SCOPE_IDENTITY()?)

The insert works fine:

MERGE [dbo].[LanguageText] AS target
USING (SELECT [Items].* from [dbo].Items ) AS source 
ON (TARGET.Id = SOURCE.LanguageTextId) 
WHEN NOT MATCHED By Target THEN 
    INSERT   
       ([Text])
 VALUES
       (source.[ItemName]);

end

But I don’t know how to update my items.Languagetextid, can I do something with:
OUTPUT $action, INSERTED.ID ?
Or is there a better way to have this done??

Thanks in advance,

Mike

Answer 1

You can do this with a merge..output to a table variable followed by an update.

SQL Fiddle

MS SQL Server 2008 Schema Setup:

create table Items
(
  ItemsId int identity primary key,
  ItemName nvarchar(50) not null,
  ItemsLanguageTextId int null
);

create table ItemsLanguageText
(
  ItemsLanguageTextId int identity primary key,
  Text nvarchar(50) not null
);

insert into Items values('Name 1', null);
insert into Items values('Name 2', null);
insert into Items values('Name 3', null);

Query 1:

declare @T table
(
  ItemsId int,
  ItemsLanguageTextId int
);

merge ItemsLanguageText as T
using (
        select ItemsId, ItemName
        from Items
        where ItemsLanguageTextId is null
      ) as S
on 0 = 1
when not matched then
  insert (Text) values (S.ItemName)
output S.ItemsId, inserted.ItemsLanguageTextId
  into @T;

update Items
set ItemsLanguageTextId = T.ItemsLanguageTextId
from @T as T
where T.ItemsId = Items.ItemsId;

Results:

Query 2:

select * from Items;

Results:

| ITEMSID | ITEMNAME | ITEMSLANGUAGETEXTID |
--------------------------------------------
|       1 |   Name 1 |                  13 |
|       2 |   Name 2 |                  14 |
|       3 |   Name 3 |                  15 |

Query 3:

select * from ItemsLanguageText;

Results:

| ITEMSLANGUAGETEXTID |   TEXT |
--------------------------------
|                  13 | Name 1 |
|                  14 | Name 2 |
|                  15 | Name 3 |