MySQL query select rows from table according to specific key that is not in another table -

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how select exams id , title (from table 'exams'), student (in table 'grades') hasn't written yet?

table: grades

+--------------+----+---- |student_number|e_id| ... +--------------+----+---- |888075        |1   | ... |888075        |2   | ... |888075        |4   | ... |637020        |2   | ... +--------------+----+----

table: exams

+----+------+ |e_id|title | +----+------+ |1   |exam 1| |2   |exam 2| |3   |exam 3| |4   |exam 4| +----+------+

in particular case expect following output student 888075:

+--+------+ |id|title | +--+------+ |3 |exam 3| +--+------+

i need inverse selection of this:

select e.e_id id, e.title title grades g left join exams e on g.e_id = e.e_id g.student_number = '888075'

your query close -- reverse joins , check null accordingly:

select e.e_id id, e.title title exams e    left join grades g on g.e_id = e.e_id       , g.student_number = '888075' g.e_id null

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