MySQL Trigger, insert,auto field unexpectedly ....

The field of a table has id,uid,name, where ID is self-increment,

CREATE TRIGGER trigger_insert_product
After INSERT on a
For each ROW
BEGIN

Insert into B (uid,name)

Select New.id as db_goods_id,

New.uid, New.name
;

END

The above trigger when the Insert event occurs in table A, the same data is inserted into table B, and the self-increment of table B is the same as table A, I don't know why this is the case, the auto value will be the same .... That's a very strange question.

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