DB2利用syscat.references递归查出他的所有关联表
找出所有的父表：

With reftables(reftabname,PRIORITY) as(Select reftabname,1 from syscat.references as refx where refx.tabname='PROJECT'union allSelect ref2.reftabname,reftables.PRIORITY+1 from reftables,syscat.references ref2 where reftables.reftabname=ref2.tabname)Select * from reftables ORDER BY PRIORITY DESC;

With reftables(tabname,PRIORITY) as(  Select tabname,1 from syscat.references as refx where refx.reftabname='PROJECT'  union all  Select ref2.tabname,reftables.PRIORITY+1 from reftables,syscat.references ref2 where reftables.tabname=ref2.reftabname and  reftables.PRIORITY<2)  Select distinct * from reftables ORDER BY PRIORITY DESC;

reftables.PRIORITY<2