MySQL 8.0

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CREATE TABLE Orders  (
  `OrderID` INTEGER,
  `OrderDate` VARCHAR(10),
  `EventID` INTEGER
);

INSERT INTO Orders 
  (`OrderID`, `OrderDate`, `EventID`)
VALUES
  ('1', '2022-01-01', '1'),
  ('2', '2022-01-12', '1'),
  ('3', '2022-01-01', '1'),
  ('4', '2022-03-10', '2'),
  ('5', '2022-03-15', '2');
CREATE TABLE Event  (
  `EventID` INTEGER,
  `NameEvent` VARCHAR(23),
  `OnSalesDate` VARCHAR(10)
);

INSERT INTO Event 
  (`EventID`, `NameEvent`, `OnSalesDate`) 
VALUES
  ('1', 'The Rolling Stones', '2022-01-01'),
  ('2', 'The Who Live in Concert', '2022-03-10');
SELECT `NameEvent`,`OnSalesDate`
, SUM(`OnSalesDate` = `OrderDate`) BoughtOnSalesDate
, SUM(`OnSalesDate` < `OrderDate`)  BoughtAfter
FROM Orders
Left JOIN Event on Orders.EventID = Event.EventID
GROUP  BY Orders.`EventID`, `NameEvent`,`OnSalesDate`
ORDER BY `OnSalesDate`;


NameEvent
OnSalesDate
BoughtOnSalesDate
BoughtAfter


The Rolling Stones
2022-01-01
2
1

The Who Live in Concert
2022-03-10
1
1

NameEvent	OnSalesDate	BoughtOnSalesDate	BoughtAfter
The Rolling Stones	2022-01-01	2	1
The Who Live in Concert	2022-03-10	1	1