SELECT 
  category_id, 
  parent_id 
FROM 
  cscart_categories 
WHERE 
  parent_id IN(
    2658, 2656, 6233, 2653, 4001, 4254, 2692, 
    2800, 2837, 2843
  )

Query time 0.00094

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "49.90"
    },
    "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": 122,
      "rows_produced_per_join": 122,
      "filtered": "100.00",
      "using_index": true,
      "cost_info": {
        "read_cost": "25.50",
        "eval_cost": "24.40",
        "prefix_cost": "49.90",
        "data_read_per_join": "723K"
      },
      "used_columns": [
        "category_id",
        "parent_id"
      ],
      "attached_condition": "(`webmarco`.`cscart_categories`.`parent_id` in (2658,2656,6233,2653,4001,4254,2692,2800,2837,2843))"
    }
  }
}

Result

category_id parent_id
2656 2653
2658 2653
2721 2653
2760 2653
2761 2653
2797 2653
2804 2653
2853 2653
9965 2653
9967 2653
9968 2653
9980 2653
2659 2656
2669 2656
2673 2656
2678 2656
2680 2656
2683 2656
2684 2656
2687 2656
2688 2656
2691 2656
2692 2656
2700 2656
2703 2656
2707 2656
2710 2656
2718 2656
2723 2656
2731 2656
2737 2656
2740 2656
2744 2656
2747 2656
2749 2656
2750 2656
2752 2656
2755 2656
2757 2656
2774 2656
2780 2656
2786 2656
9251 2656
9252 2656
9254 2656
9972 2656
2657 2658
2661 2658
2671 2658
2695 2658
2722 2658
2724 2658
2729 2658
2763 2658
2767 2658
2769 2658
2789 2658
2800 2658
2812 2658
2822 2658
2829 2658
2837 2658
2843 2658
2849 2658
8851 2658
9250 2658
9257 2658
9276 2658
9574 2658
9990 2658
10562 2658
10563 2658
2694 2692
2697 2692
2898 2837
2900 2837
2902 2837
2903 2837
2904 2837
2905 2837
2907 2837
2850 2843
2857 2843
2858 2843
2862 2843
2866 2843
2884 2843
4003 4001
4254 4001
4315 4001
9987 4001
4268 4254
4286 4254
4431 4254
4475 4254
4510 4254
4561 4254
4587 4254
4765 4254
4808 4254
4859 4254
4915 4254
4974 4254
5022 4254
5068 4254
5110 4254
5272 4254
5307 4254
5324 4254
6022 4254
6164 4254
6233 4254
7017 4254
7045 4254
7067 4254
7103 4254
6309 6233
7184 6233
7199 6233
7213 6233
7270 6233