Select all records from Table 1 but only the row in Table 2 with the max Version number - sql

Question

I have Table Trades.Transaction and Table Trades.BondRef. They can be joined on InstrumentDescription but produce one to many rows as there are multiple ISIN/CUSIP (BondRef) per InstrumentDescription (Transaction). I would like to join but only display the row from Trades.BondRefwhich has the max Version number. I have reviewed numerous posts and come up with the code below.
SELECT tr.TradeDate,
tr.InstrumentDescription,
B.maxVersion,
B.IsLatest,
B.Isin,
B.Cusip,
B.RbcType1,
B.RbcType2,
B.RbcType3
FROM [trade_management].[dbo].[Trades.Transaction] tr WITH (NOLOCK)
INNER JOIN (
SELECT InstrumentDescription,
MAX(version) maxVersion,
IsLatest,
Isin,
Cusip,
RbcType1,
RbcType2,
RbcType3
FROM [trade_management].[dbo].[Trades.BondRef]
WHERE ValidTo between '2018-10-30 00:00:00.0000000 +00:00' and '2018-10-30 23:59:29.0000000 +00:00'
GROUP BY InstrumentDescription,IsLatest, Isin,Cusip,RbcType1,RbcType2,RbcType3
) AS B
ON B.InstrumentDescription = tr.InstrumentDescription
WHERE
(tr.OrigSystem = 'RBCE TOMS' OR tr.OrigSystem = 'SALE')
and (BookingAccountType = 'CLIENT' OR BookingAccountType = 'MASTER')
and tr.BookingAccountFacilitatorTeamCode in ('ESF','MJC','43B','DWV','G9J','698','9DN','A2T','AX3') -- HK Sales
and tr.IsLatest = 1
and tr.Status not in ('Cancelled')
and tr.TradeDate between '2018-10-30 00:00:00.0000000 +00:00' and '2018-10-30 23:59:29.0000000 +00:00'
order by tr.tradedate
I'm getting duplicate rows being returned as my groupby includes the Isin and Cusip. Note CBAAU 4 1/2 12/09/25 with Version 249 should be the only row returned.
TradeDate InstrumentDescription maxVersion Isin Cusip RbcType1 RbcType2 RbcType3
2018-10-30 NESNVX 3 1/8 03/22/23 124 XS1796233150 NULL CORP INDUSTRIAL EURO_MTN
2018-10-30 HSBC 6 1/4 PERP 116 US404280BN80 404280BN8 CORP BANK GLOBAL
2018-10-30 CBAAU 4 1/2 12/09/25 248 US2027A0HR32 2027A0HR3 CORP BANK PRIV_PLACEMENT
2018-10-30 CBAAU 4 1/2 12/09/25 249 US2027A1HR15 2027A1HR1 CORP BANK EURO-DOLLAR
2018-10-30 EIB 8 3/4 08/18/25 434 XS1274823571 NULL SUPRA NATIONAL EURO_MTN
But if I remove them I can display the fields.
Column 'trade_management.dbo.Trades.BondRef.Isin' is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause.
So how can I retrieve the columns in Trades.BondRef in the Select staement if they are not included in the subquery?

Answer 1

Instead of using a GROUP BY and a MAX you could use the window function ROW_NUMBER.
Since ROW_NUMBER can be given an order.
To determine which record will have row_number = 1.
And you can also combine an ORDER BY ROW_NUMBER with a TOP 1 WITH TIES.
...
INNER JOIN (
SELECT TOP 1 WITH TIES
InstrumentDescription,
version AS maxVersion,
IsLatest,
Isin,
Cusip,
RbcType1,
RbcType2,
RbcType3
FROM [trade_management].[dbo].[Trades.BondRef]
WHERE ValidTo between '2018-10-30 00:00:00.0000000 +00:00' and '2018-10-30 23:59:29.0000000 +00:00'
ORDER BY ROW_NUMBER() OVER (PARTITION BY InstrumentDescription ORDER BY version DESC)
) AS B
ON B.InstrumentDescription = tr.InstrumentDescription
...

Answer 2

You don't do anything to remove any non-maximum versions. If you can use common-table expressions then this is just another step, to find the maximum version per instrument description:
WITH B AS ( SELECT InstrumentDescription,
MAX(version) maxVersion,
IsLatest,
Isin,
Cusip,
RbcType1,
RbcType2,
RbcType3
FROM [trade_management].[dbo].[Trades.BondRef]
WHERE ValidTo between '2018-10-30 00:00:00.0000000 +00:00' and '2018-10-30 23:59:29.0000000 +00:00'
GROUP BY InstrumentDescription,IsLatest, Isin,Cusip,RbcType1,RbcType2,RbcType3),
C AS (
SELECT *, ROW_NUMBER() OVER (PARTITION BY InstrumentDescription ORDER BY maxVersion DESC) AS version_id FROM B)
SELECT tr.TradeDate,
tr.InstrumentDescription,
C.maxVersion,
C.IsLatest,
C.Isin,
C.Cusip,
C.RbcType1,
C.RbcType2,
C.RbcType3
FROM [trade_management].[dbo].[Trades.Transaction] tr WITH (NOLOCK)
INNER JOIN C
ON C.InstrumentDescription = tr.InstrumentDescription AND c.version_id = 1
WHERE
(tr.OrigSystem = 'RBCE TOMS' OR tr.OrigSystem = 'SALE')
and (BookingAccountType = 'CLIENT' OR BookingAccountType = 'MASTER')
and tr.BookingAccountFacilitatorTeamCode in ('ESF','MJC','43B','DWV','G9J','698','9DN','A2T','AX3') -- HK Sales
and tr.IsLatest = 1
and tr.Status not in ('Cancelled')
and tr.TradeDate between '2018-10-30 00:00:00.0000000 +00:00' and '2018-10-30 23:59:29.0000000 +00:00'
order by tr.tradedate