Transact SQL :: Update Incoming Rows Based On Percentage Calculation

This is on SQL Server 2008. Please find a detailed description and the file of the data, that I am working on.

Requirements:

1.
If
'Channel'
is
not
equal to "Omnibus"
where
the 'Trans Description'is
equal to "Purchase"
and
"Redemption"
for
one purchase and
one redemption that match on 'System'
,
'Account TA Number'
,
'Product Name'
,
'Settled Date'
,
and
where
the 'Trade Amount'
of the purchase and
redemption is
within 5%,
then
display those set of records.

2.
If
deemed wash trades,
allow user to update the purchase and
redemption pair 'Trans Description'
from
"Purchase"
to "Exchange In"
and
'Trans Description'
from
"Redemption"
with
"Exchange out"

System Channel Dealer Name Firm Name Product Cusip Product Name Product Share Class Trade ID Settled Date Account TA Number Trans Description  Trade Amount 

SCHWABPORTAL US - ASG MILLIMAN MILLIMAN 64128K777 Strategic Income Fund A 29806259 30-Jan-15 000BY00F2RW Redemption  $      25,68,458.15

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