sql = <<-SQL
                    (users.id IN (
                      SELECT user_purposes.user_id
                      FROM user_purposes
                      WHERE user_purposes.purpose_id IN (:purposes)
                      AND user_purposes.user_id = users.id
                    ))
                  SQL

   (27.8ms)  SELECT COUNT(DISTINCT "users"."id") FROM "users" LEFT OUTER JOIN "user_purposes" ON "user_purposes"."user_id" = "users"."id" LEFT OUTER JOIN "purposes" ON "purposes"."id" = "user_purposes"."purpose_id" WHERE ( (users.id IN (
 SELECT user_purposes.user_id
 FROM user_purposes
 WHERE user_purposes.purpose_id IN ('1','2')
 AND user_purposes.user_id = users.id
 ))
)
  SQL (37.0ms)  SELECT DISTINCT "users".id, "users"."id" AS alias_0 FROM "users" LEFT OUTER JOIN "user_purposes" ON "user_purposes"."user_id" = "users"."id" LEFT OUTER JOIN "purposes" ON "purposes"."id" = "user_purposes"."purpose_id" WHERE ( (users.id IN (
 SELECT user_purposes.user_id
 FROM user_purposes
 WHERE user_purposes.purpose_id IN ('1','2')
 AND user_purposes.user_id = users.id
 ))
) ORDER BY "users"."id" DESC LIMIT 15 OFFSET 0





                  sql = <<-SQL
                    (EXISTS (
                      SELECT * FROM user_purposes
                      WHERE user_purposes.user_id = users.id
                      AND user_purposes.purpose_id IN (:purposes)
                    ))
                  SQL

   (0.5ms)  SELECT COUNT(DISTINCT "users"."id") FROM "users" LEFT OUTER JOIN "user_purposes" ON "user_purposes"."user_id" = "users"."id" LEFT OUTER JOIN "purposes" ON "purposes"."id" = "user_purposes"."purpose_id" WHERE ( (EXISTS (
 SELECT * FROM user_purposes
 WHERE user_purposes.user_id = users.id
 AND user_purposes.purpose_id IN ('1','2')
 ))
)
  SQL (0.4ms)  SELECT DISTINCT "users".id, "users"."id" AS alias_0 FROM "users" LEFT OUTER JOIN "user_purposes" ON "user_purposes"."user_id" = "users"."id" LEFT OUTER JOIN "purposes" ON "purposes"."id" = "user_purposes"."purpose_id" WHERE ( (EXISTS (
 SELECT * FROM user_purposes
 WHERE user_purposes.user_id = users.id
 AND user_purposes.purpose_id IN ('1','2')
 ))
) ORDER BY "users"."id" DESC LIMIT 15 OFFSET 0