2.1 内连接
select a.*,b.* FROM a INNER join b ON a.id = b.id; 查出所有
或者 select a.*,b.* FROM a join b on a.id=b.id
效果:
2.2 外连接 http://blog.csdn.net/jintao_ma/article/details/51260458
2.1 内连接
select a.*,b.* FROM a INNER join b ON a.id = b.id; 查出所有
或者 select a.*,b.* FROM a join b on a.id=b.id
效果:
2.2 外连接 http://blog.csdn.net/jintao_ma/article/details/51260458