sql - Mysql mulitple row insert-select statement with last_insert_id()

Question

Ok. So the short of it is, I was trying to do an INSERT SELECT such as:

START TRANSACTION;  
INSERT INTO dbNEW.entity (commonName, surname)  
SELECT namefirst, namelast  
FROM dbOLD.user;  
SET @key = LAST_INSERT_ID();  
INSERT INTO dbNEW.user (userID, entityID, other)  
SELECT user_id, @key, other  
FROM dbOLD.user;  
COMMIT;

Of course @key does not return each subsequent LAST_INSERT_ID() from each insert but the ID from only the last insert.

Basically, I'm splitting an old USER Table into an ENTITY and USER like:

 dbOLD.user
 +-------------+---------------------+------+-----+------------+----------------+
 | Field       | Type                | Null | Key | Default    | Extra          |
 +-------------+---------------------+------+-----+------------+----------------+
 | user_id     | int(10) unsigned    | NO   | PRI | NULL       | auto_increment |
 | namefirst   | varchar(20)         | NO   |     |            |                |
 | namelast    | varchar(20)         | NO   |     |            |                |
 | other       | varchar(10)         | NO   |     |            |                |
 +-------------+---------------------+------+-----+------------+----------------+


 dbNEW.user
 +-------------+---------------------+------+-----+------------+----------------+
 | Field       | Type                | Null | Key | Default    | Extra          |
 +-------------+---------------------+------+-----+------------+----------------+
 | userID      | int(10) unsigned    | NO   | PRI | NULL       | auto_increment |
 | entityID    | int(10) unsigned    | NO   | MUL | 0          |                |
 | other       | varchar(10)         | NO   |     |            |                |
 +-------------+---------------------+------+-----+------------+----------------+


 dbNEW.entity
 +--------------+---------------------+------+-----+------------+----------------+
 | Field        | Type                | Null | Key | Default    | Extra          |
 +--------------+---------------------+------+-----+------------+----------------+
 | entityID     | int(10) unsigned    | NO   | PRI | NULL       | auto_increment |
 | commonName   | varchar(20)         | NO   |     |            |                |
 | surname      | varchar(20)         | NO   |     |            |                |
 +--------------+---------------------+------+-----+------------+----------------+

Why would I want to do this? Basically, I have a "STORE" entity which is going to have fields common to "USERS" such as address and phone number. So any "ENTITY" might have none to multiple addresses (shipping, billing, mailing) and none to multiple phone numbers (fax, main, billing, cell, home) There may be other ways to accomplish this, but this is the solution I ended up with.

The STOREs and USERS from the old db need to keep their old PKs and gain an additional ENTITY fk. How can I do this without making a dump and manually editing it?

Answer 1

For the last query, use this

INSERT INTO dbNEW.`user` (userID, entityID, other)  
SELECT user_id, entityID, other
FROM
(
    SELECT user_id, @key + @rn entityID, other, @rn := @rn + 1
    FROM (select @rn:=0) x, dbOLD.`user`
    order by user_id
) y;

The LAST_INSERT_ID() in MySQL is the FIRST id created in a batch, unlike SCOPE_IDENTITY() in SQL Server which is the LAST id. Since it is the first, we increment each row using the variable @rn, starting at addition=0 for the first row.