摘要：
表A lefttable,表B righttableleft join: 与right join 相类似，反之亦然。1. select lefttable.*,righttable.* from lefttable left join righttable on lefttable.id = righttable.id and righttable.name = "xxx" where lefttable.name = "XXX";2. select lefttable.*,righttable.* from lefttableleft joinrigh 阅读全文
