ALTER TABLE "materials"
  ADD COLUMN IF NOT EXISTS "task_detail_requester_user_id" TEXT,
  ADD COLUMN IF NOT EXISTS "task_detail_requester_name" TEXT;

CREATE INDEX IF NOT EXISTS "materials_task_detail_requester_user_id_idx"
  ON "materials" ("task_detail_requester_user_id");

DO $$
BEGIN
  IF NOT EXISTS (
    SELECT 1
    FROM pg_constraint
    WHERE conname = 'materials_task_detail_requester_user_id_fkey'
  ) THEN
    ALTER TABLE "materials"
      ADD CONSTRAINT "materials_task_detail_requester_user_id_fkey"
      FOREIGN KEY ("task_detail_requester_user_id")
      REFERENCES "users"("id")
      ON DELETE SET NULL
      ON UPDATE CASCADE;
  END IF;
END
$$;