mysql 树状结构

create procedure Pro_GetUnderOrg(in userid varchar(50))
begin
declare lev int;
set lev=1;
drop table if exists tmp1;
    CREATE TABLE tmp1(`ID` BIGINT,LoginID VARCHAR(50),Username varchar(50),pre_LoginID varchar(50) ,levv INT);
    INSERT tmp1 SELECT `ID`, LoginID,Username,pre_LoginID,1 FROM tbUsers WHERE pre_LoginID=userid;
while  row_count()>0
do
     set lev=lev+1;
     INSERT tmp1 SELECT t.`ID`, t.LoginID,t.Username,t.pre_LoginID,lev from tbUsers t join tmp1 a on t.pre_LoginID=a.LoginID AND levv=lev-1;
end while ;
    INSERT tmp1 SELECT `ID`,LoginID,Username,pre_LoginID,0 FROM tbUsers WHERE LoginID=userid;
     SELECT * FROM tmp1 where LoginID <>userid;/*这一步是为了去除自己*/
end;