sql - Join without specyfing primary and foreign key -

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is possible (ex. in ms sql) perform join in way this:

select p.* person p join order o

by default db engine relation between tables , use without writing additional: 

on p.id = o.fk_person

no need specify join clause in on of 2 ways.

implicit join notation:

select p.*  person p, order o p.id = o.fk_person

or explicit join notation:

select p.*  person p inner join order o         on p.id = o.fk_person

if won't specify join order, no server join anything. it's defined in sql standard.


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