Optimizer table elimination suggestion

I believe it will be easy, if you implement following cases for optimizer table elimination:
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create view v_xxx as

select
   id,
   (select first_name from users where id = products.user) as product
from
   products;
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then user can do:

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select id from v_xxx ;
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this case is almost identical to left outher join you already implemented. You do not need to know "first_name" column. Is eighter set or is NULL.