create database row;
use row;
create table person (id int, name varchar(50));
insert into person values (1, 'bob');
insert into person values (2, 'sam');
insert into person values (3, 'jim');
create table crew (boat_id int, man1_id int, man2_id int, man3_id int);
insert into crew values (1, 1, 2, 3);
select
  boat_id,
  man1_id,
  person1.name as man1_name,
  man2_id,
  person2.name as man2_name,
  man3_id,
  person3.name as man3_name
from
  crew left join
  person person1 on crew.man1_id = person1.id left join
  person person2 on crew.man2_id = person2.id left join
  person person3 on crew.man3_id = person3.id;