SELECT 
  product_id 
FROM 
  cscart_mb_ali_products 
WHERE 
  product_id IN (
    18797, 18798, 18799, 18800, 18801, 18802, 
    18803, 18804, 18805, 18806, 18807, 
    18808, 18809, 18810, 18811, 18812
  )

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_mb_ali_products",
      "access_type": "range",
      "possible_keys": ["product_id"],
      "key": "product_id",
      "key_length": "4",
      "used_key_parts": ["product_id"],
      "rows": 16,
      "filtered": 100,
      "attached_condition": "cscart_mb_ali_products.product_id in (18797,18798,18799,18800,18801,18802,18803,18804,18805,18806,18807,18808,18809,18810,18811,18812)",
      "using_index": true
    }
  }
}