相同表结构

INSERT INTO table1 SELECT * FROM table2;

不同表结构

INSERT INTO table1(filed1, ..., filedn) SELECT table2.filed1, ..., table2.filedn FROM table2;

不同数据库

INSERT into db1.table1(id, number, name) 
  SELECT stu.person_id
     , stu.number
     , person.name
FROM db2.t_stu_info AS stu
    , db2.t_person_info as person
    WHERE stu.person_id = person.id