MySQL 8.0

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CREATE TABLE `event1` (
  `FirstName` varchar(45) NOT NULL,
  `LastName` varchar(15) NOT NULL,
  `City` varchar(50) NOT NULL,
  `Attending` tinyint DEFAULT NULL,
  `AdultsInvited` smallint DEFAULT NULL,
  `ChildrenInvited` smallint DEFAULT NULL,
  `AdultsAttending` smallint DEFAULT NULL,
  `ChildrenAttending` smallint DEFAULT NULL
);

INSERT INTO `event1` (`FirstName`, `LastName`, `City`, `Attending`, `AdultsInvited`, `ChildrenInvited`, `AdultsAttending`, `ChildrenAttending`) VALUES
('a', '2', 'c2', 0, 4, 2, 0, 0),
('a', '3', 'c3', 0, 6, 3, 0, 0),
('Event', '1', 'City', NULL, 5, 3, NULL, NULL),
('Event', 'All', 'City', NULL, 65, 66, NULL, NULL),
('Friend', '1', 'City', NULL, 56, 5, NULL, NULL);

SELECT * FROM event1;

CREATE TABLE `event2` (
  `FirstName` varchar(45) NOT NULL,
  `LastName` varchar(15) NOT NULL,
  `City` varchar(50) NOT NULL,
  `Attending` tinyint DEFAULT NULL,
  `AdultsInvited` smallint DEFAULT NULL,
  `ChildrenInvited` smallint DEFAULT NULL,
  `AdultsAttending` smallint DEFAULT NULL,
  `ChildrenAttending` smallint DEFAULT NULL
);

INSERT INTO `event2` (`FirstName`, `LastName`, `City`, `Attending`, `AdultsInvited`, `ChildrenInvited`, `AdultsAttending`, `ChildrenAttending`) VALUES
('a', '1', 'c1', 0, 2, 1, 0, 0),
('a', '3', 'c3', 0, 6, 3, 0, 0),
('Event', '2', 'City', NULL, 5, 0, NULL, NULL),
('Event', 'All', 'City', NULL, 6, 3, NULL, NULL),
('Friend', '1', 'City', NULL, 3, 66, NULL, NULL);

SELECT * FROM event2;

FirstName	LastName	City	Attending	AdultsInvited	ChildrenInvited	AdultsAttending	ChildrenAttending
a	2	c2	0	4	2	0	0
a	3	c3	0	6	3	0	0
Event	1	City	null	5	3	null	null
Event	All	City	null	65	66	null	null
Friend	1	City	null	56	5	null	null

FirstName	LastName	City	Attending	AdultsInvited	ChildrenInvited	AdultsAttending	ChildrenAttending
a	1	c1	0	2	1	0	0
a	3	c3	0	6	3	0	0
Event	2	City	null	5	0	null	null
Event	All	City	null	6	3	null	null
Friend	1	City	null	3	66	null	null

FirstName	LastName	City	AdultsInvited	AdultsInvited
a	1	c1	null	2
a	2	c2	4	null
a	3	c3	6	6
Event	1	City	5	null
Event	2	City	null	5
Event	All	City	65	6
Friend	1	City	56	3