SELECT 
  id_path 
FROM 
  cscart_categories 
WHERE 
  category_id IN (
    1, 20, 30, 42, 43, 44, 48, 60, 71, 73, 75, 
    123, 194, 217, 233, 236, 237, 238, 241, 
    242, 258, 259, 261, 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 (1,20,30,42,43,44,48,60,71,73,75,123,194,217,233,236,237,238,241,242,258,259,261,306)"
    }
  }
}