OUTPUT INSERTED FROM Source Table Column [duplicate] - sql-server

Question

I've made some modifications to my database and I need to migrate the old data to the new tables. For that, I need to fill a table (ReportOptions) taking the data from the original table (Practice), and fill a second intermediate table (PracticeReportOption).
ReportOption (
ReportOptionId int PK,
field1, field2...
)
Practice (
PracticeId int PK,
field1, field2...
)
PracticeReportOption (
PracticeReportOptionId int PK,
PracticeId int FK,
ReportOptionId int FK,
field1, field2...
)
I made a query to get all the data I need to move from Practice to ReportOptions, but I'm having trouble filling the intermediate table.
--Auxiliary tables
DECLARE #ReportOption TABLE (
PracticeId int, -- This field is not on the actual ReportOption table
field1, field2...
)
DECLARE #PracticeReportOption TABLE (
PracticeId int,
ReportOptionId int,
field1, field2
)
--First I get all the data I need to move
INSERT INTO #ReportOption
SELECT P.practiceId, field1, field2...
FROM Practice P
--I insert it into the new table,
--but somehow I need to have the repation PracticeId / ReportOptionId
INSERT INTO ReportOption (field1, field2...)
OUTPUT #ReportOption.PracticeId, --> this is the field I don't know how to get
inserted.ReportOptionId
INTO #PracticeReportOption (PracticeId, ReportOptionId)
SELECT field1, field2
FROM #ReportOption
-- This would insert the relationship, If I knew how to get it!
INSERT INTO #PracticeReportOption (PracticeId, ReportOptionId)
SELECT PracticeId, ReportOptionId
FROM #ReportOption
If I could reference a field that is not from the destination table in the OUTPUT clause, that would be great (I think I can't, but I don't know for sure). Any ideas on how to accomplish my need?

Answer 1

You can do this by using MERGE instead of INSERT.
So replace this:
INSERT INTO ReportOption (field1, field2...)
OUTPUT #ReportOption.PracticeId, --> this is the field I don't know how to get
inserted.ReportOptionId
INTO #PracticeReportOption (PracticeId, ReportOptionId)
SELECT field1, field2
FROM #ReportOption
with:
MERGE INTO ReportOption USING #ReportOption AS temp ON 1 = 0
WHEN NOT MATCHED THEN
INSERT (field1, field2)
VALUES (temp.Field1, temp.Field2)
OUTPUT temp.PracticeId, inserted.ReportOptionId, inserted.Field1, inserted.Field2
INTO #PracticeReportOption (PracticeId, ReportOptionId, Field1, Field2);
The key is to use a predicate that will never be true (1 = 0) in the merge search condition, so you will always perform the insert, but have access to fields in both the source and destination tables.
Here is the entire code I used to test it:
CREATE TABLE ReportOption (
ReportOptionID INT IDENTITY(1, 1),
Field1 INT,
Field2 INT
)
CREATE TABLE Practice (
PracticeID INT IDENTITY(1, 1),
Field1 INT,
Field2 INT
)
CREATE TABLE PracticeReportOption (
PracticeReportOptionID INT IDENTITY(1, 1),
PracticeID INT,
ReportOptionID INT,
Field1 INT,
Field2 INT
)
INSERT INTO Practice VALUES (1, 1), (2, 2), (3, 3), (4, 4)
MERGE INTO ReportOption r USING Practice p ON 1 = 0
WHEN NOT MATCHED THEN
INSERT (field1, field2)
VALUES (p.Field1, p.Field2)
OUTPUT p.PracticeId, inserted.ReportOptionId, inserted.Field1, inserted.Field2
INTO PracticeReportOption (PracticeId, ReportOptionId, Field1, Field2);
SELECT *
FROM PracticeReportOption
DROP TABLE ReportOption
DROP TABLE Practice
DROP TABLE PracticeReportOption
More reading, and the source of all that I know on the subject is here.

Answer 2

Maybe someone who uses MS SQL Server 2005 or lower will find this answer useful.
MERGE will only work for SQL Server 2008 or higher.
For the rest, I found another workaround which will give you the ability to create kind of mapping tables.
Here's how Resolution will look like for SQL 2005:
DECLARE #ReportOption TABLE (
ReportOptionID INT IDENTITY(1, 1),
Field1 INT,
Field2 INT
)
DECLARE #Practice TABLE(
PracticeID INT IDENTITY(1, 1),
Field1 INT,
Field2 INT
)
DECLARE #PracticeReportOption TABLE(
PracticeReportOptionID INT IDENTITY(1, 1),
PracticeID INT,
ReportOptionID INT,
Field1 INT,
Field2 INT
)
INSERT INTO #Practice (Field1, Field2) VALUES (1, 1)
INSERT INTO #Practice (Field1, Field2) VALUES (2, 2)
INSERT INTO #Practice (Field1, Field2) VALUES (3, 3)
INSERT INTO #Practice (Field1, Field2) VALUES (4, 4)
INSERT INTO #ReportOption (field1, field2)
OUTPUT INSERTED.ReportOptionID, INSERTED.Field1, INSERTED.Field2
INTO #PracticeReportOption (ReportOptionID, Field1, Field2)
SELECT Field1, Field2
FROM #Practice
ORDER BY PracticeID ASC;
WITH CTE AS (
SELECT PracticeID,
ROW_NUMBER() OVER ( ORDER BY PracticeID ASC ) AS ROW
FROM #Practice
)
UPDATE M
SET M.PracticeID = S.PracticeID
FROM #PracticeReportOption AS M
JOIN CTE AS S ON S.ROW = M.PracticeReportOptionID
SELECT * FROM #PracticeReportOption
The main trick is that we are filling the mapping table twice with ordered data from the source and destination table.
For more details, see Merging Inserted Data Using OUTPUT in SQL Server 2005.