Question

i have two tables:

new_table

id | parentid | f1 | f2 | customerid

initial_table (does not have customerid)

id | parentid | f1 | f2

what i need to do is move ALL items from initial_table to new_table. however, id’s change (auto generated) in the new_table!

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so, my idea (for now) is:

1 – move all data except id and parentid from initial_table to new_table

2 – use a lookup_table with

id | originalparentid | newparentid | customerid

3 – go through the lookup_table and update the new_table parentid column with the new parentid‘s

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so…

question – 1 – is this the right way?

question – 2a – if yes, how to do it?

question – 2b – if no, how then?

the problem in 2 is that i am doing this from a trigger and customerid is SELECT @customerid = id FROM inserted and this is fine. then i am doing

INSERT INTO new_table (f1, f2, customerid)
SELECT f1, f2 @customerid FROM initial_table

but i don’t get the new id’s from new_table when i do it like that.

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so, please, help me write this trigger:

i need to copy all data from initial_table to new_table with the problem that the id’s will change and i need to update the parentid’s accordingly in the new_table

thnx

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here is my current trigger:

ALTER TRIGGER Copy
ON dbo.Customers

FOR INSERT
AS

BEGIN TRANSACTION

/* variables */
DECLARE
    @customerid bigint

SELECT @customerid = id FROM inserted

/* insert all for this customer */
INSERT INTO new_table (f1, f2, customerid)
    SELECT f1, f2 @customerid FROM initial_table

/* TODO: add entries to lookup table */

/* TODO: fix the pages' parentid's */

/* execute */
COMMIT TRANSACTION

GO

Answer 1

I would just turn IDENTITY INSERT off for the initial insert and avoid this whole mess. Is there any reason you can’t do that? Something like this should do it:

SET IDENTITY_INSERT dbo.Customers ON

Then when you are done just run

SET IDENTITY_INSERT dbo.Customers OFF