SELECT 
  COUNT(*) 
FROM 
  cscart_wishlist_items 
WHERE 
  product_id IN (7349)

Query time 0.00370

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "355.39"
    },
    "table": {
      "table_name": "cscart_wishlist_items",
      "access_type": "ALL",
      "rows_examined_per_scan": 3521,
      "rows_produced_per_join": 352,
      "filtered": "10.00",
      "cost_info": {
        "read_cost": "320.18",
        "eval_cost": "35.21",
        "prefix_cost": "355.39",
        "data_read_per_join": "5K"
      },
      "used_columns": [
        "product_id"
      ],
      "attached_condition": "(`cscartdb`.`cscart_wishlist_items`.`product_id` = 7349)"
    }
  }
}