MySQL 8.0

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create table coachs(coach varchar(50),team varchar(10), wins int, year int)
create table teams(team varchar(10),worldcupwin varchar(10),year int)
insert into coachs(coach,team,wins,year) values
('nk01','a',4,2000),
('vx92','b',1,2000),
('nk01','b',5,2003),
('vx92','a',2,2003)
insert into teams(team ,worldcupwin ,year)
values
('a','Y',2000),
('b','N',2000),
('a','Y',2003),
('b','N',2003)
 SELECT c.year, c.team
          FROM coachs AS c inner join teams t on c.team = t.team and c.year=t.year
          WHERE c.year >= 1999 and exists (select 1 from coachs c1 where c.team=c1.team 
          and c.year=c1.year
          having max(c1.wins)=c.wins) 
and t.worldcupwin = 'Y'


year
team


2000
a

2003
a