SELECT 
  @row_number:=CASE WHEN(
    @group_n1 COLLATE utf8mb4_unicode_ci = town
    AND
    @group_n2 COLLATE utf8mb4_unicode_ci = village
  ) THEN(@row_number + 1) ELSE(1) END AS row_number,
  @sum_num:=CASE WHEN(
    @group_n1 COLLATE utf8mb4_unicode_ci = town
    AND
    @group_n2 COLLATE utf8mb4_unicode_ci = village
  ) THEN(@sum_num + IFNULL(num, 0)) ELSE(1) END AS sum_number,
  @group_n1:=town AS group_n1,
  @group_n2:=village AS group_n2,
  t.*
FROM (
  SELECT * FROM fydj_address
  ORDER BY town, village, last_edit_time DESC
) AS t, (
  SELECT
    @row_number:=0, @sum_num:=0,
    @group_n1:='', @group_n2:=''
) AS tmp
;

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