SELECT "posts".* FROM "posts" WHERE "posts"."id" IN (SELECT post_id FROM "posts" INNER JOIN "comments" ON "comments"."post_id" = "posts"."id" WHERE "comments"."title" = 'foo') AND "posts"."id" IN (SELECT post_id FROM "posts" INNER JOIN "comments" ON "comments"."post_id" = "posts"."id" WHERE "comments"."title" = 'bar')