ช่วยหน่อยครับ ผมมีชุดข้อมูล json แต่อยากปลิ้นออกมาเป็นจำนวนตัวเลข

JSON ครับ
{
"select * from data  where product = 'xxx' and data->> 'type'='Monitor'": [
	{
		"id" : 684886,  //ID ที่1
		"product" : "xxxx",
		"data" : "{\"id\": \"002F000C424E430220313031\", \"afr\": 14.699999809265, \"car\": \"yamaha\"}",
		"created_at" : "2019-04-09T13:19:11Z"
	},
	{
		"id" : 645534,  //ID ที่2
		"product" : "xxxx",
		"data" : "{\"id\": \"002F000C424E430220313031\", \"afr\": 14.699999809265, \"car\": \"yamaha\"}",
		"created_at" : "2019-04-09T13:19:11Z"
	},
	{
		"id" : 678245,
		"product" : "xxxx",  //ID ที่3
		"data" : "{\"id\": \"002F000C424E430220313031\", \"afr\": 14.699999809265, \"car\": \"yamaha\"}",
		"created_at" : "2019-04-09T13:19:11Z"
	},
	{
		"id" : 623452,  //ID ที่4
		"product" : "xxxx",
		"data" : "{\"id\": \"002F000C424E430220313031\", \"afr\": 14.699999809265, \"car\": \"yamaha\"}",
		"created_at" : "2019-04-09T13:19:11Z"
	}	
]}