all_backups=($(find /mnt/save -not -path '*/\.*' -type f | sort -r))
for ((i=${#all_backups[@]}-1; i>50; i--)); do
   echo rm old backpu ${all_backups[i]} >&2
   rm -f ${all_backups[i]}  || true
done

for b in "${all_backups[@]}"; do
   if [ -n "$b" ]; then
      du -sh "$b"
      if ! du -sh "$b" | grep -Ei "^[ \t]*[0-9][0-9]*[0-9]?(.0)?[mg]"; then
         echo would rm empty backup $b >&2
         set -x
         mv "$b" "${b%/*}/.${b##*/}"
         set +x
         continue
      fi
      echo restoring $b >&2
      if psql $DATABASE_URL < "$b"; then
         break
      fi
   fi
done
service postgresql start