SELECT 
  id_path 
FROM 
  cscart_categories 
WHERE 
  category_id IN (
    15, 17, 18, 19, 38, 49, 57, 67, 73, 81, 82, 
    87, 123, 208, 210, 217, 228, 233, 234, 
    235, 236, 264, 304, 306
  )

Query time 0.00049

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_categories",
      "access_type": "range",
      "possible_keys": ["PRIMARY"],
      "key": "PRIMARY",
      "key_length": "3",
      "used_key_parts": ["category_id"],
      "rows": 24,
      "filtered": 100,
      "index_condition": "cscart_categories.category_id in (15,17,18,19,38,49,57,67,73,81,82,87,123,208,210,217,228,233,234,235,236,264,304,306)"
    }
  }
}