mysql - Return result depend on conditions for multible rows without self join -


i have large answers table this

person_id|question_id|answer 1|101|6 1|102|2 1|103|5     2|101|2 2|102|5 2|103|5     3|101|2 3|102|8 3|103|6     4|101|2 4|102|8 4|103|6 4|101|6 4|102|2 4|103|5

how return persons depend on multiple question answers? example need return person answers:

6 question 101   , 2 question 102   , 5 question 103

the query should return person 1 , 4

and consider need filter depend on 10 questions, don't need 10 self join on table :)

you can using group by , having:

select person_id t (question_id, answer) in ( (101, 6), (102, 2), (103, 5) ) group person_id having count(distinct question_id) = 3;

note "3" needs match number of questions have in in list.


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