MySQL 5.6

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create table `pt_products` (
  `id` int(6) unsigned NOT NULL,
  `ean` bigint(13) unsigned NOT NULL,
  `merchant` varchar(64) NOT NULL,
  `price` decimal(10,2)NOT NULL,
  PRIMARY KEY (`id`)
);

INSERT INTO `pt_products` (`id`, `ean`, `merchant`, `price`) VALUES
 ('1', '884116311874', 'Amazon', '10000.00'),
 ('2', '884116311874', 'BestBuy', '10999.00'),
 ('3','884116321378', 'CyberPuerta', '14789.00'),
 ('4', '884116311875', 'Amazon', '10999.00'),
 ('5', '884116311875', 'BestBuy', '10000.00'),
('94918', '10343943707','TankePc', '3834.00'),
('94919', '10343943708','Amazon', '9999.99'),
 ('94913', '10343943704','XtremeTecPc', '3834.00'),
 ('93885', '10343943704','Linio', '3999.00'),
 ('87448', '10343943704','Amazon',  '3259.00'),
 ('87617','10086100372', 'Amazon', '959.00'  ),
 ('87618', '10086100372','Tecnocom', '900.00'  );
create table graph (
    id int primary key auto_increment,
    ean bigint(13) unsigned not null,
    avg_price decimal(10,2) not null,
   created_at timestamp default current_timestamp
);

insert into graph(ean, avg_price)
select ean, avg(price) avg_price
from pt_products
group by ean;
select * from graph


id
ean
avg_price
created_at


1
10086100372
929.50
2020-06-11 18:01:59

2
10343943704
3697.33
2020-06-11 18:01:59

3
10343943707
3834.00
2020-06-11 18:01:59

4
10343943708
9999.99
2020-06-11 18:01:59

5
884116311874
10499.50
2020-06-11 18:01:59

6
884116311875
10499.50
2020-06-11 18:01:59

7
884116321378
14789.00
2020-06-11 18:01:59

id	ean	avg_price	created_at
1	10086100372	929.50	2020-06-11 18:01:59
2	10343943704	3697.33	2020-06-11 18:01:59
3	10343943707	3834.00	2020-06-11 18:01:59
4	10343943708	9999.99	2020-06-11 18:01:59
5	884116311874	10499.50	2020-06-11 18:01:59
6	884116311875	10499.50	2020-06-11 18:01:59
7	884116321378	14789.00	2020-06-11 18:01:59