1、项目在eclipse中存在的位置
workspace\.metadata\.plugins\org.eclipse.core.resources\.projects
2、oracle的左连接写法
select * from t_snc sp,t_trans_port t1 ,t_trans_port t2,t_snc_ext ex
where sp.snc_id = ex.snc_id(+)
and sp.a_port_id = t1.port_id
and sp.z_port_id = t2.port_id