Sql compare tables and insert missing data

[PAVB]

Homework, huh?

Okay ... there are a lot of unknowns in those business specs - like datatypes, complete table structures, etc - so, here you have a template - after all, your instructor really wants you to do at least part of it, isn't it?

insert
into    
    item_a
select  
    *
from
(
    select  *
    from    item
    where   i_id like '25%'
    minus
    select  *
    from    item_a
    where   i_id like '25%'
);