Grouping Inner Query based on a column.Please help

Question

I have a strange query.
I am using Subquery to display the count of rows from the inner query
depending upon the value of 'Y' or 'N'
Trade
id_entity       id_inst_code_type   id_inst_code   dt_trade
AGL            SE                  5660249        10-Feb-06
AGL            SE                  5660249        13-Feb-06
AGL            SE                  5660249        13-Feb'06
Instrument_xref
ID_inst      id_inst_xref_type     id_inst_xref  flg_active
0029010             SE          5660249          Y
0070789          SE          5660249          Y
0071190          SE          5660249          Y
0072385          SE          5660249          Y
0073215          SE          5660249          Y
0084797          SE          5660249          Y
0091375          SE          5660249          Y
0094690          SE          5660249          Y
0104438          SE          5660249          Y
My output:
id_inst_code_type          id_inst_code   Earliest    Latest       Total    Active
SE                         5660249       10 Feb 06   13 Feb 06    3        9
2) If all the 'flg_active' column in Table Instrument_xref is set to 'N'
   the Active should be 0.
3) Assume that the flg_active could be 3 Y's and 6 N's then what?
id_inst_code_type          id_inst_code   Earliest    Latest       Total    Active
SE                         5660249       10 Feb 06   13 Feb 06    3        0
How do I check for the 'Y' or 'N' value in my code below ?
Help appreciated as the the functionality changes by the hour...
select    tie.id_entity             'Entity',
          tie.id_inst_code          'Inst Code',
          min(tie.dt_trade)         'Earliest',
          max(tie.dt_trade)         'Latest',
          count(*)                  'Total',
          dt.InnerTotal             'Active'   
from     trade_input_event tie,
(Select  insx.id_inst_xref_type,
               insx.id_inst_xref,
               insx.flg_active,
               count(*) InnerTotal
  from instrument_xref insx
  where insx.id_inst_xref = '5660249'
  ---** Do I need to Check the flg_active here..
  ---** Do I need to use the Having clause here? ie having count(insx.id_inst_xref) = 'N'
   group by insx.id_inst_xref_type,insx.id_inst_xref,insx.flg_active) dt
  where tie.id_inst_code = dt.id_inst_xref
  and tie.id_entity = 'AGL'
  group by tie.id_entity, tie.id_inst_code_type,tie.id_inst_code

Answer 1

As the flg_active is set to 'Y', I am trying to set it to 'N' in the query
so that count of 0 is returned, but this displays nothing.
Please help as to how to display a count(*) of 0 when the flg_active is 'N'??
Select  insx.id_inst_xref_type,
               insx.id_inst_xref,
               insx.flg_active,
               count(*) InnerTotal
  from instrument_xref insx
  where insx.id_inst_xref = '5660249'
  and insx.flg_active = 'N'
  group by insx.id_inst_xref_type,insx.id_inst_xref,insx.flg_active) dt