SELECT 
  category_id, 
  parent_id 
FROM 
  cscart_categories 
WHERE 
  parent_id IN(
    3057, 3019, 3016, 2775, 2776, 2773, 2782, 
    2772, 2779, 2778, 2789, 3015, 2781, 
    2780, 2777, 2783, 2788, 2925, 3056, 
    2774, 2771, 1491, 2769, 2786, 2022, 
    2794, 3095
  )

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "28.36"
    },
    "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": 48,
      "rows_produced_per_join": 48,
      "filtered": "100.00",
      "index_condition": "(`cscart_db`.`cscart_categories`.`parent_id` in (3057,3019,3016,2775,2776,2773,2782,2772,2779,2778,2789,3015,2781,2780,2777,2783,2788,2925,3056,2774,2771,1491,2769,2786,2022,2794,3095))",
      "cost_info": {
        "read_cost": "23.56",
        "eval_cost": "4.80",
        "prefix_cost": "28.36",
        "data_read_per_join": "134K"
      },
      "used_columns": [
        "category_id",
        "parent_id"
      ]
    }
  }
}