Distinct and Group By are going to give you different results. To get the results you expect you’ll want to use
Person.group(:name).count
(1.2ms) SELECT COUNT(*) AS count_all, name AS name FROM "people" GROUP BY "people"."name"
=> {"Dan"=>3, "Dave"=>2, "Vic"=>1}
Seen above, group will return things as a hash. While distinct just returns the number of people in total, seen below.
Person.distinct(:name).count (0.4ms) SELECT DISTINCT COUNT(DISTINCT "people"."id") FROM "people" => 6
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