MySQL 8.0

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create table RunnerActions (Runner varchar(100), Action varchar(100));
insert into RunnerActions values ('John','Start');
insert into RunnerActions values ('Amy','Start');
insert into RunnerActions values ('Susan','Start');
insert into RunnerActions values ('John','Finish');
insert into RunnerActions values ('Amy','Start');
insert into RunnerActions values ('Amy','Finish');
SELECT 
RUNNER, 
COUNT(CASE WHEN Action = 'Start' THEN 1 END) AS StartCount,
COUNT(CASE WHEN Action = 'Finish' THEN 1 END) AS FinishCount
FROM RunnerActions
GROUP BY
RUNNER
HAVING COUNT(CASE WHEN Action = 'Start' THEN 1 END) > 
COUNT(CASE WHEN Action = 'Finish' THEN 1 END);


RUNNER
StartCount
FinishCount


Amy
2
1

Susan
1
0


SELECT 
RUNNER, 
SUM(Action = 'Start') AS StartCount,
SUM(Action = 'Finish') AS FinishCount
FROM RunnerActions
GROUP BY
RUNNER
HAVING 
SUM(Action = 'Start') > 
SUM(Action = 'Finish');


RUNNER
StartCount
FinishCount


Amy
2
1

Susan
1
0