关联Left Outer Join的第一条记录

数据准备

CREATE TABLE person
    (person_id int primary key, firstname varchar2(4), lastname varchar2(9))
/
INSERT ALL
    INTO person (person_id, firstname, lastname)
         VALUES (1, 'john', 'lennon')
    INTO person (person_id, firstname, lastname)
         VALUES (2, 'paul', 'mccartney')
SELECT * FROM dual;
 
CREATE TABLE address
    (person_id int, address_id int primary key, city varchar2(8))
/
INSERT ALL
    INTO address (person_id, address_id, city)
         VALUES (1, 1, 'new york')
    INTO address (person_id, address_id, city)
         VALUES (1, 2, 'england')
    INTO address (person_id, address_id, city)
         VALUES (1, 3, 'japan')
    INTO address (person_id, address_id, city)
         VALUES (2, 4, 'london')
SELECT * FROM dual;

 select  
 
      p.person_id, p.firstname, p.lastname,
 
      x.recent_city
 
    from person p
    left join (
 
        select person_id,      
 
            min(city) -- can change this to max(city). will work regardless of min/max
 
            -- important you do this to get the recent: keep(dense_rank last)
 
            keep(dense_rank last order by address_id)
               as recent_city
 
        from address
        group by person_id
 
    ) x on x.person_id = p.person_id

Live test: http://www.sqlfiddle.com/#!4/7b1c9/2