在Postgresql版本12.2

Question

我们正在将Oracle迁移到Postgresql 12.2。我们知道Postgresql中没有使用Merge。相反，我们必须使用upsert，在冲突中插入。但我们收到语法错误。这是代码。

MERGE INTO itmmasprc m
      USING(SELECT rec.xncPRCNEW   AS IMPPRCNEW,
                    rec.xncUPDDT    AS IMPUPDDT,
                    rec.xncCMT      AS IMPCMT,
                    rec.xncNEWSTRDT AS IMPNEWSTRDT,
                    rec.xncNEWENDDT AS IMPNEWENDDT
               ) h
      ON ((m.IMPITMID = loc_IMPVDRITMID or m.IMPVDRITMID = loc_IMPVDRITMID)
      AND m.IMPVDRID = loc_VDRID AND (coalesce(m.IMPSITE, 0) = coalesce(loc_IMPSITE, 0) or coalesce(m.IMPZONE, 0) = coalesce(loc_IMPSITE, 0)) and m.IMPEDDT = TO_DATE(rec.xncCSENDT, 'MM/DD/YYYY'))
      WHEN MATCHED THEN
        UPDATE
           SET m.IMPCHG    = h.IMPPRCNEW,
               m.IMPSTS    = CASE WHEN CASE WHEN loc_autoapp=1 THEN  'VP'  ELSE 'SB' END ='SB' THEN (CASE WHEN loc_count=0 THEN  'SB'  ELSE 'VP' END )  ELSE CASE WHEN loc_autoapp=1 THEN  'VP'  ELSE 'SB' END  END ,
               m.IMPCSENDT = to_date(h.IMPNEWENDDT, 'MM/DD/YYYY'),

      WHEN NOT MATCHED THEN
        INSERT(IMPID,
           IMPSTS,
           IMPDPTID,
           IMPCREDT,
           IMPUPDBY,
           IMPUPDDT,
           IMPVDRCCNO)
        VALUES
          (nextval('mass_purchaseprice_sqn'),
           trim(both substr(rec.xncitmid,
                       INSTR(rec.xncitmid, ']', 1, 3) + 1,
                       300)),
           round((rec.xncPRCNEW)::numeric, 2),
           substr(rec.xncbuyrid,
                  INSTR(rec.xncbuyrid, ' ', 1, 1) + 1,
                  (INSTR(rec.xncbuyrid, '-', 1, 1) -
                  (INSTR(rec.xncbuyrid, ' ', 1, 1)) - 2)),

           CASE WHEN CASE WHEN loc_autoapp=1 THEN  'VP'  ELSE 'SB' END ='SB' THEN (CASE WHEN loc_count=0 THEN  'SB'  ELSE 'VP' END )  ELSE CASE WHEN loc_autoapp=1 THEN  'VP'  ELSE 'SB' END  END ,
           PK_VP_COSTUPLOAD.f_get_dept(loc_IMPVITMID,
                                       rec.xncUPC,
                                       loc_VDRID),
           (select vdrccno
              from vdrgen
             where vdrextno =
                   substr(rec.xncvdrid,
                          1,
                          position(' - ' in rec.xncvdrid) - 1)));

            RAISE NOTICE 'test3';