select - SQL count on a joined table -


i've got 2 tables, 1 persons , 1 relationships.

i want retrieve person children.

currently i'm joining tables this:

select     persons.id,     persons.native_country,     relationships.person_id,     relationships.relation  persons inner join relationships on relationships.person_id = id                              , relationships.relation = 'child';

now i'm trying count persons.id , max, not sure how that.

you can try using group by:

select persons.id, count(*) "no of children" persons inner join relationships on relationships.person_id = id , relationships.relation = 'child' group persons.id;


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