Bizarre set of SQL results...

Here's the first statement:
select DCII.SEQ_NBR, count(1)
FROM PS_DEM_CHG_INF_INV DCII , PS_PL_TRANS_IT_OPT PTIO
WHERE DCII.SCHED_DATE >= '2004-10-05'
AND DCII.SCHED_DATE <= '2007-10-05'
AND DCII.DEMAND_SOURCE = 'PL'
AND DCII.PROCESSED_FLG <> 'C'
AND PTIO.PROBINST = 'COMBE_1005'
AND DCII.BUSINESS_UNIT = PTIO.BUS_UNIT_SOURCE
AND DCII.DESTIN_BU = PTIO.BUSINESS_UNIT
AND DCII.INV_ITEM_ID = PTIO.INV_ITEM_ID
AND DCII.SHIP_TYPE_ID = PTIO.SHIP_TYPE_ID
AND (EXISTS (
SELECT 'X' FROM PS_PL_BU_ITEMS
WHERE PROBINST = 'COMBE_1005'
AND BUSINESS_UNIT = DCII.BUSINESS_UNIT
AND INV_ITEM_ID = DCII.INV_ITEM_ID
AND 'Y' = 'Y')
OR EXISTS (
SELECT 'X' FROM PS_PL_BU_ITEMS
WHERE PROBINST = 'COMBE_1005'
AND BUSINESS_UNIT = DCII.DESTIN_BU
AND INV_ITEM_ID = DCII.INV_ITEM_ID
AND 'Y' = 'Y'))
group by DCII.SEQ_NBR
having count(1) > 1
one of the resulting rows is:
110441,2
so then I alter the SQL to get some deatil on the duplicate SEQ_NBR
above as follows:
select *
FROM PS_DEM_CHG_INF_INV DCII , PS_PL_TRANS_IT_OPT PTIO
WHERE DCII.SCHED_DATE >= '2004-10-05'
AND DCII.SCHED_DATE <= '2007-10-05'
AND DCII.DEMAND_SOURCE = 'PL'
AND DCII.PROCESSED_FLG <> 'C'
AND PTIO.PROBINST = 'COMBE_1005'
AND DCII.BUSINESS_UNIT = PTIO.BUS_UNIT_SOURCE
AND DCII.DESTIN_BU = PTIO.BUSINESS_UNIT
AND DCII.INV_ITEM_ID = PTIO.INV_ITEM_ID
AND DCII.SHIP_TYPE_ID = PTIO.SHIP_TYPE_ID
AND (EXISTS (
SELECT 'X' FROM PS_PL_BU_ITEMS
WHERE PROBINST = 'COMBE_1005'
AND BUSINESS_UNIT = DCII.BUSINESS_UNIT
AND INV_ITEM_ID = DCII.INV_ITEM_ID
AND 'Y' = 'Y')
OR EXISTS (
SELECT 'X' FROM PS_PL_BU_ITEMS
WHERE PROBINST = 'COMBE_1005'
AND BUSINESS_UNIT = DCII.DESTIN_BU
AND INV_ITEM_ID = DCII.INV_ITEM_ID
AND 'Y' = 'Y'))
and DCII.SEQ_NBR = 110441
when I execute the above statement, I only get 1 row. Based on the
count from the 1st statement, I would expect 2. Can anyone come up with
an explanation for that?Sorry - false alarm - just require and UPDATE STATISTICS.