SELECT 
  category_id, 
  parent_id 
FROM 
  cscart_categories 
WHERE 
  parent_id IN(
    29952, 7168, 5549, 2545, 2546, 7167, 
    881, 7219, 5715, 5442, 6941, 28993, 
    1162, 929, 16597, 16604, 15692, 6394, 
    15711, 29508, 6447, 5706, 3945, 29000, 
    28996, 6633, 29002, 29003, 2548, 2620, 
    6382, 6431, 15718, 16612, 29004, 9646, 
    6397, 8786, 6848, 29008, 28998, 917, 
    2494, 30406, 29006, 29001, 16599, 30497, 
    5770, 16587, 2526, 2784, 6403, 29012, 
    29020, 933, 6366, 29011, 1095, 29021, 
    15688, 29016, 29013, 6444, 7226, 29005, 
    6406, 6640, 28999, 30487, 29028, 16592, 
    15699, 29018, 8831, 30504, 29030, 7170, 
    6451, 7227, 16610, 14451, 29031, 29015, 
    30494, 6442, 29022, 29007, 915, 916, 
    1096, 30488, 28991, 7379, 11406, 29713
  )

Query time 0.00108

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "28.68"
    },
    "table": {
      "table_name": "cscart_categories",
      "access_type": "range",
      "possible_keys": [
        "parent"
      ],
      "key": "parent",
      "used_key_parts": [
        "parent_id"
      ],
      "key_length": "3",
      "rows_examined_per_scan": 142,
      "rows_produced_per_join": 142,
      "filtered": "100.00",
      "using_index": true,
      "cost_info": {
        "read_cost": "14.49",
        "eval_cost": "14.20",
        "prefix_cost": "28.69",
        "data_read_per_join": "368K"
      },
      "used_columns": [
        "category_id",
        "parent_id"
      ],
      "attached_condition": "(`maniamall_cscart`.`cscart_categories`.`parent_id` in (29952,7168,5549,2545,2546,7167,881,7219,5715,5442,6941,28993,1162,929,16597,16604,15692,6394,15711,29508,6447,5706,3945,29000,28996,6633,29002,29003,2548,2620,6382,6431,15718,16612,29004,9646,6397,8786,6848,29008,28998,917,2494,30406,29006,29001,16599,30497,5770,16587,2526,2784,6403,29012,29020,933,6366,29011,1095,29021,15688,29016,29013,6444,7226,29005,6406,6640,28999,30487,29028,16592,15699,29018,8831,30504,29030,7170,6451,7227,16610,14451,29031,29015,30494,6442,29022,29007,915,916,1096,30488,28991,7379,11406,29713))"
    }
  }
}

Result

category_id parent_id
915 881
929 881
933 881
2620 881
5770 881
6366 881
6848 881
7170 881
7227 881
916 915
917 915
1096 1095
2526 1095
2548 1095
6633 1095
3945 1162
6394 6382
6397 6382
6406 6403
6442 6403
6444 6403
6447 6403
6640 6403
7379 6403
6451 6431
11406 6431
28993 28991
28996 28993
28998 28993
28999 28993
29001 28993
29002 28993
29003 28993
29004 28993
29006 28993
29007 28993
29008 28993
29011 28993
29012 28993
29013 28993
29015 28993
29016 28993
29018 28993
29020 28993
29021 28993
29022 28993
29028 28993
29030 28993
29031 28993
30406 28993
30487 28993
29000 28999
29005 28999
30488 30487
30494 30487
30497 30487
30504 30487