ex.sql

SELECT
   "class"."id" AS "class_id",
   "class"."createdAt" AS "class_createdAt",
   "class"."updatedAt" AS "class_updatedAt",
   "class"."title" AS "class_title"
  
FROM
   "class" "class" 
   INNER JOIN
      "time_availability" "timeAvailability" 
      ON "timeAvailability"."classId" = "class"."id" 
   INNER JOIN
      "class_picture" "pictures" 
      ON "pictures"."classId" = "class"."id" 
   INNER JOIN
      "file" "file"
      ON "pictures"."fileId" = "pictures"."fileId" 
   INNER JOIN
      "class_extra_detail" "classExtraDetails" 
      ON "classExtraDetails"."classId" = "class"."id"