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MySQL [tree]> create table node_tree (id int not null primary key,node_name varchar(128) not null default "",up_node_id int,node_level char(1));

MySQL [tree]> insert into node_tree values (1,"jx",null,"1"),(2,'jx.webserver', 1, '2'),(3,'jx.webserver.nginx1', 2, '3'),(4,'jx.logserver', 1, '2');

查询jx的从表

MySQL [tree]> select nt.node_name from node_tree,node_tree as nt where node_tree.node_name="jx" and node_tree.id=nt.up_node_id;

MySQL [tree]> select                                                                       
    -> node_tree1.id as  主表ID,
    -> node_tree1.name as 主表名字, 
    -> node_tree2.name  as 从表名字,
    -> node_tree2.up_id  as 从表上级ID 
    -> 
    -> from node_tree1, node_tree2 
    -> 
    -> where node_tree1.name='jx' and node_tree1.id= node_tree2.up_id;

查询jx.webserver的主表

MySQL [tree]> select a.node_name from node_tree a ,node_tree b where b.node_name="jx.webserver" and b.up_node_id=a.id;