sql - How to select the latest rows where each contains one value of all possible values found in a domain table? -

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id username city        registeryear 1  user1    new york    1990 2  user2    san diego   2008 3  user3    chicago     2009 4  user4    los angeles 1994 5  user5    san diego   2004

domain table

id  city 1   new york 2   san diego 3   los angeles 4   chicago

in example query return:

user1 user2 user3 user4

well, first need replace "city" in first table id column of domain table. "city" not primary key.

after that:

select u.username   users u,        domain d  d.id = u.cityid        , u.registeryear = (select max(u2.registeryear)                                users u2                               u2.cityid = u.cityid);

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