SELECT 
  category_id, 
  parent_id 
FROM 
  cscart_categories 
WHERE 
  parent_id IN(
    10300, 4805, 4808, 4431, 10438, 4313, 
    3087, 4321, 4525, 2916, 10334, 2944, 
    4334, 6809, 5495, 356, 3080, 2912, 3105, 
    2760, 2920, 3741, 7435, 3224, 7135, 
    266, 4257, 3228, 4564, 10437, 7080, 
    4787, 4973, 3231, 10335, 3002, 3631, 
    4317, 6975, 3085, 2653, 2917, 5506, 
    3535, 6426, 4003, 6340, 4910, 7008, 
    7464, 5821, 393, 6448, 4001, 4254, 5522, 
    6536, 6471, 5362, 3591, 5577, 5098, 
    3532, 6870, 3144, 2910, 7242, 5152, 
    6980, 3648, 9720, 5372, 1936, 5457, 
    7454, 3046, 3185, 3617, 5684, 6288, 
    3048, 5847, 4271, 2601, 6328, 6473, 
    5742, 5030, 6343, 9697, 7797, 8356, 
    3487, 2851, 3685, 6928
  )

Query time 0.00376

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "440.61"
    },
    "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": 1097,
      "rows_produced_per_join": 1097,
      "filtered": "100.00",
      "using_index": true,
      "cost_info": {
        "read_cost": "221.21",
        "eval_cost": "219.40",
        "prefix_cost": "440.61",
        "data_read_per_join": "6M"
      },
      "used_columns": [
        "category_id",
        "parent_id"
      ],
      "attached_condition": "(`webmarco`.`cscart_categories`.`parent_id` in (10300,4805,4808,4431,10438,4313,3087,4321,4525,2916,10334,2944,4334,6809,5495,356,3080,2912,3105,2760,2920,3741,7435,3224,7135,266,4257,3228,4564,10437,7080,4787,4973,3231,10335,3002,3631,4317,6975,3085,2653,2917,5506,3535,6426,4003,6340,4910,7008,7464,5821,393,6448,4001,4254,5522,6536,6471,5362,3591,5577,5098,3532,6870,3144,2910,7242,5152,6980,3648,9720,5372,1936,5457,7454,3046,3185,3617,5684,6288,3048,5847,4271,2601,6328,6473,5742,5030,6343,9697,7797,8356,3487,2851,3685,6928))"
    }
  }
}