mysql - Querying a 1 to many table where the many side has at least one row -


have common schema, 2 tables.

users table contains columns id, name. checkins table contains columns user_id, checkin_date.

in hypothetical, users can have many instances of rows in checkins table.

checkin_date in case of type date

i want able query users have @ minimum 1 checkin in checkins table checkin after 2016.

i suggest using exists:

select u.* users u exists (select 1               checks c               c.user_id = u.id , c.checkin_date >= '2016-01-01'              );

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