SELECT 
  product_id 
FROM 
  cscart_product_popularity 
WHERE 
  product_id IN (
    262398, 262852, 262853, 262854, 262855, 
    262856, 262857, 262858, 262859
  )

Query time 0.00047

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "4.62"
    },
    "table": {
      "table_name": "cscart_product_popularity",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY",
        "total"
      ],
      "key": "total",
      "used_key_parts": [
        "product_id"
      ],
      "key_length": "3",
      "rows_examined_per_scan": 9,
      "rows_produced_per_join": 9,
      "filtered": "100.00",
      "using_index": true,
      "cost_info": {
        "read_cost": "2.82",
        "eval_cost": "1.80",
        "prefix_cost": "4.62",
        "data_read_per_join": "288"
      },
      "used_columns": [
        "product_id"
      ],
      "attached_condition": "(`webmarco`.`cscart_product_popularity`.`product_id` in (262398,262852,262853,262854,262855,262856,262857,262858,262859))"
    }
  }
}