foreign keys - Why can't I SELECT a parent field that doesn't have a child? -

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(rest_branches) table of restaurants.

(phone_numbers) table contains restaurants phone_numbers, , has field called (branch_id) references restaurant id.

when try:

select *  rest_branches natural join phone_numbers

i restaurants have phone_number. should restaurants if don't have phone number?

because that's how inner/natural joins work. if wanted restaurants, use left join instead , specify join condition.


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