Query to find match on two fields where third does not..

Question

Struggling with this one..
Stripped down example data
SECTION     GROUPID     SUBGROUPID     COMPONENT     PNUM     USERNAME
HVAC     AC     MOTOR          HOSE          111.1     BOB
HVAC     AC     MOTOR          HOSE          111.2     BOB
HVAC     AC     MOTOR          HOSE          111.3     JIM
HVAC     AC     MOTOR          BOLT          411     BOB
HVAC     AC     MOTOR          BOLT          411     BOB
HVAC     AC     MOTOR          BOLT          411     BOB
HVAC     AC     MOTOR          BOLT          (null)     (null)
HVAC     AC     MOTOR          CLAMP          211.1     BOB
HVAC     AC     MOTOR          CLAMP          211.2     JIM
HVAC     AC     MOTOR          CLAMP          211.3     BOB
HVAC     AC     MOTOR          STRAP          611.1     JIM
HVAC     AC     MOTOR          BELT          811.3     BOB
HVAC     AC     MOTOR          BELT          (null)     (null)
HVAC     AC     MOTOR          DISC          (null)     (null)
HVAC     AC     MOTOR          DISC          (null)     (null)
HVAC     AC     MOTOR          DISC          (null)     (null)
     What I need to get, is a list of records where the GroupID and Component Matched, and where they had a PNUM that were not all the same
So in this case I would only want these returned, Section/SubgroupID/Username are not needed to match on anything, but here to visualize the
extra data that can be there. Items that have PNUM that IS NULL need to be ignored? Example would be the intance where above the PNUM
for one record was 811.3 while the one below it was null, that should not return back. Its considered "ok" and does not need to be reported.
SECTION     GROUPID     SUBGROUPID     COMPONENT     PNUM     USERNAME
HVAC     AC     MOTOR          HOSE          111.1     BOB
HVAC     AC     MOTOR          HOSE          111.2     BOB
HVAC     AC     MOTOR          HOSE          111.3     JIM
HVAC     AC     MOTOR          CLAMP          211.1     BOB
HVAC     AC     MOTOR          CLAMP          211.2     JIM
HVAC     AC     MOTOR          CLAMP          211.3     BOB

Answer 1

maybe this.
SQL> select section, groupid, subgroupid, component, pnum, username
  2    from (select section, groupid, subgroupid, component, pnum, username,
  3                 count(pnum) over (partition by groupid, component, pnum order by groupid, component, pnum) cnt1,
  4                 count(pnum) over (partition by groupid, component order by groupid, component) cnt2
  5            from (select 'HVAC' section, 'AC' groupid, 'MOTOR' subgroupid, 'HOSE'  component, 111.1  pnum, 'BOB'  username from dual union all
  6                  select 'HVAC' section, 'AC' groupid, 'MOTOR' subgroupid, 'HOSE'  component, 111.2  pnum, 'BOB'  username from dual union all
  7                  select 'HVAC' section, 'AC' groupid, 'MOTOR' subgroupid, 'HOSE'  component, 111.3  pnum, 'JIM'  username from dual union all
  8                  select 'HVAC' section, 'AC' groupid, 'MOTOR' subgroupid, 'BOLT'  component, 411    pnum, 'BOB'  username from dual union all
  9                  select 'HVAC' section, 'AC' groupid, 'MOTOR' subgroupid, 'BOLT'  component, 411       pnum, 'BOB'  username from dual union all
10                  select 'HVAC' section, 'AC' groupid, 'MOTOR' subgroupid, 'BOLT'  component, 411       pnum, 'BOB'  username from dual union all
11                  select 'HVAC' section, 'AC' groupid, 'MOTOR' subgroupid, 'BOLT'  component, (null) pnum, (null) username from dual union all
12                  select 'HVAC' section, 'AC' groupid, 'MOTOR' subgroupid, 'CLAMP' component, 211.1  pnum, 'BOB'  username from dual union all
13                  select 'HVAC' section, 'AC' groupid, 'MOTOR' subgroupid, 'CLAMP' component, 211.2  pnum, 'JIM'  username from dual union all
14                  select 'HVAC' section, 'AC' groupid, 'MOTOR' subgroupid, 'CLAMP' component, 211.3  pnum, 'BOB'  username from dual union all
15                  select 'HVAC' section, 'AC' groupid, 'MOTOR' subgroupid, 'STRAP' component, 611.1  pnum, 'JIM'  username from dual union all
16                  select 'HVAC' section, 'AC' groupid, 'MOTOR' subgroupid, 'BELT'  component, 811.3  pnum, 'BOB'  username from dual union all
17                  select 'HVAC' section, 'AC' groupid, 'MOTOR' subgroupid, 'BELT'  component, (null) pnum, (null) username from dual union all
18                  select 'HVAC' section, 'AC' groupid, 'MOTOR' subgroupid, 'DISC'  component, (null) pnum, (null) username from dual union all
19                  select 'HVAC' section, 'AC' groupid, 'MOTOR' subgroupid, 'DISC'  component, (null) pnum, (null) username from dual union all
20                  select 'HVAC' section, 'AC' groupid, 'MOTOR' subgroupid, 'DISC'  component, (null) pnum, (null) username from dual)) vt
21  where vt.cnt1 = 1
22    and vt.cnt2 > 1
23  order by vt.pnum;
SECTION GROUPID SUBGROUPID COMPONENT       PNUM USERNAME
HVAC    AC      MOTOR      HOSE           111.1 BOB
HVAC    AC      MOTOR      HOSE           111.2 BOB
HVAC    AC      MOTOR      HOSE           111.3 JIM
HVAC    AC      MOTOR      CLAMP          211.1 BOB
HVAC    AC      MOTOR      CLAMP          211.2 JIM
HVAC    AC      MOTOR      CLAMP          211.3 BOB
6 rows selected
SQL>