T-SQL insert and update foreign key without cursor

Question

I have two tables in MS SQL:

CREATE TABLE Table1 (ID INT IDENTITY(1,1) NOT NULL, TEXTVal VARCHAR(100), Table2Id int)

insert into Table1 (TEXTVal) values('aaa'); 
insert into Table1 (TEXTVal) values('bbb'); insert into Table1 (TEXTVal) values('ccc');


CREATE TABLE Table2 (ID INT IDENTITY(1,1) NOT NULL, TEXTVal VARCHAR(100), Table2Id int)

Id are identity columns. I want to copy TEXTVal values from Table1 to Table2:

INSERT INTO Table2 (TEXTVal)
SELECT TEXTVal FROM Table1
where TEXTVal <> 'ccc'

and after that update column Table2Id in Table1 with appropriate values of Id from Table2. I can do this with cursor and SCOPE_IDENTITY().

I am just wondering, is there a way to do it without cursor in T-SQL?

Answer 1

As Jeroen stated in comments, you'll want to use OUTPUT. In the following example if you don't have an AdventureWorks database, just use a test database. You should be able to copy/paste this and just run it to see it in action!

USE AdventureWorks;
GO
----Creating the table which will store permanent table
CREATE TABLE TestTable (ID INT, TEXTVal VARCHAR(100))
----Creating temp table to store ovalues of OUTPUT clause
DECLARE @TmpTable TABLE (ID_New INT, TEXTVal_New VARCHAR(100),ID_Old INT, TEXTVal_Old VARCHAR(100))
----Insert values in real table
INSERT TestTable (ID, TEXTVal)
VALUES (1,'FirstVal')
INSERT TestTable (ID, TEXTVal)
VALUES (2,'SecondVal')
----Update the table and insert values in temp table using Output clause
UPDATE TestTable
SET TEXTVal = 'NewValue'
OUTPUT Inserted.ID, Inserted.TEXTVal, Deleted.ID, Deleted.TEXTVal INTO @TmpTable
WHERE ID IN (1,2)
----Check the values in the temp table and real table
----The values in both the tables will be same
SELECT * FROM @TmpTable
SELECT * FROM TestTable
----Clean up time
DROP TABLE TestTable
GO

ResultSet:

TmpTable:
ID_New TextVal_New ID_Old TextVal_Old
——————— ——————— ——————— ———————
1 NewValue 1 FirstVal
2 NewValue 2 SecondVal

Original Table:
ID TextVal
——————— ———————
1 NewValue
2 NewValue

As you can see it is possible to capture new values, and the values you are updating. In this example I'm just stuffing them into a table variable but you could do whatever you'd like with them. :)