SELECT 
  product_id 
FROM 
  cscart_product_popularity 
WHERE 
  product_id IN (
    12969, 12970, 12971, 12972, 12973, 12961, 
    12962, 12963, 12964, 12965, 12966, 
    12967, 12968
  )

Query time 0.00054

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "2.92"
    },
    "table": {
      "table_name": "cscart_product_popularity",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY",
        "total"
      ],
      "key": "PRIMARY",
      "used_key_parts": [
        "product_id"
      ],
      "key_length": "3",
      "rows_examined_per_scan": 13,
      "rows_produced_per_join": 13,
      "filtered": "100.00",
      "using_index": true,
      "cost_info": {
        "read_cost": "1.62",
        "eval_cost": "1.30",
        "prefix_cost": "2.92",
        "data_read_per_join": "416"
      },
      "used_columns": [
        "product_id"
      ],
      "attached_condition": "(`test2_gaseus`.`cscart_product_popularity`.`product_id` in (12969,12970,12971,12972,12973,12961,12962,12963,12964,12965,12966,12967,12968))"
    }
  }
}

Result

product_id
12961
12962
12963
12964
12965
12966
12967
12968
12969
12970
12971
12972
12973