一种方法使用 row_number() :

with q as (
      <your query here>
     )
select q.*
from (select q.*,
             row_number() over (partition by npd, shortstringvalue order by oid desc) as seqnum
      from q
     ) q
where seqnum = 1;

从oracle 12c开始，您还可以使用：

select . . .
from . . .
order by row_number() over (partition by npd, shortstringvalue order by oid desc)
fetch first 1 row with ties;

请使用下面的查询。你必须使用 row_number() .

select 
    oid, npd, shortstringvalue 
from
    (Select distinct 
         pl.oid, pr.npd, sch.shortstringvalue, 
         row_number() over (partition by pr.npd, sch.shortstringvalue order by sch.shortstringvalue) as rnk
     from 
         sonpda_rdb.jpipelinesystem pl
     join 
         sonpda_rdb.xsystemhierarchy xsys1 on xsys1.oidorigin = pl.oid
     join 
         sonpda_rdb.jnameditem it1 on it1.oid = pl.oid
     join 
         sonpda_rdb.jrtepiperun pr on pr.oid = xsys1.oiddestination
     join 
         sonpda_rdb.jnameditem it2 on it2.oid = pr.oid
     join 
         sonpda_rdb.xownsparts xop on xop.oidorigin = pr.oid
     join 
         sonpda_rdb.jrtestockpartoccur stckprt on stckprt.oid = xop.oiddestination
     join 
         sonpda_rdb.xmadefrom xmf on xmf.oidorigin = stckprt.oid
     join 
         sonpda_rdb.jdpipecomponent pipcmp on pipcmp.oid = xmf.oiddestination
     join 
         sonpda_rdb.cl_schedulethickness sch on sch.valueid = pipcmp.firstsizeschedule
     where 
         it1.itemname = 'C-8001') query 
where 
    rnk = 1
order by 
    npd desc;