Query in SQL (SCCM Database) that selects only the newest record when there is a duplicate

Question

I need to modify the following query to select only the records with the newest LastLogin if the BIOSSerialNumber is duplicated. I have tried the solutions proposed in similar questions (row_number(), subqueries,...), but I'm not able to make it work.

It's a SQL query to the SCCM database:

SELECT 
v_GS_COMPUTER_SYSTEM.Name0 as name,
v_GS_COMPUTER_SYSTEM_PRODUCT.Version0 as model,
v_GS_COMPUTER_SYSTEM.ResourceID,
v_GS_SYSTEM.SystemRole0 as SystemRole,
v_GS_OPERATING_SYSTEM.Caption0 as caption,
v_GS_SYSTEM_ENCLOSURE.ChassisTypes0 as chassistype,
v_GS_WORKSTATION_STATUS.LastHWScan, 
v_GS_PC_BIOS.SerialNumber0 as BIOSSerialNumber,
v_GS_COMPUTER_SYSTEM_PRODUCT.UUID0 as UUIDSerialNumber,
v_GS_SYSTEM_ENCLOSURE.SerialNumber0 as ChassisSerialNumber,
v_GS_BASEBOARD.SerialNumber0 as BaseboardSerialNumber,
v_R_SYSTEM.Last_Logon_Timestamp0 as LastLogin

FROM v_GS_COMPUTER_SYSTEM
LEFT JOIN v_GS_WORKSTATION_STATUS ON v_GS_COMPUTER_SYSTEM.ResourceID = v_GS_WORKSTATION_STATUS.ResourceID 
LEFT JOIN v_GS_SYSTEM ON v_GS_COMPUTER_SYSTEM.ResourceID = v_GS_SYSTEM.ResourceID 
LEFT JOIN v_GS_PC_BIOS ON v_GS_COMPUTER_SYSTEM.ResourceID = v_GS_PC_BIOS.ResourceID
LEFT JOIN v_GS_OPERATING_SYSTEM ON v_GS_COMPUTER_SYSTEM.ResourceID = v_GS_OPERATING_SYSTEM.ResourceID
LEFT JOIN v_GS_COMPUTER_SYSTEM_PRODUCT ON v_GS_COMPUTER_SYSTEM.ResourceID = v_GS_COMPUTER_SYSTEM_PRODUCT.ResourceID
LEFT JOIN v_GS_SYSTEM_ENCLOSURE ON v_GS_COMPUTER_SYSTEM.ResourceID = v_GS_SYSTEM_ENCLOSURE.ResourceID
LEFT JOIN v_GS_BASEBOARD ON v_GS_COMPUTER_SYSTEM.ResourceID = v_GS_BASEBOARD.ResourceID
LEFT JOIN v_R_SYSTEM ON v_GS_COMPUTER_SYSTEM.ResourceID = v_R_SYSTEM.ResourceID

If the result is:

name    model   ResourceID  …   BIOSSerialNumber    …   LastLogin
ABC-123 HP XYZ  567845678   …   SerialNumber1       …   2020-10-26 21:14:28.000
DEF-456 HP XYZ  984567432   …   SerialNumber1       …   2020-10-24 07:32:05.000
EFG-789 HP XYZ  127687643   …   SerialNumber2       …   2020-10-21 08:35:05.000

I need to return only rows 1 and 3 because row 2 has same BIOSSerialNumber as 1 but the LastLogin is older:

name    model   ResourceID  …   BIOSSerialNumber    …   LastLogin
ABC-123 HP XYZ  567845678   …   SerialNumber1       …   2020-10-26 21:14:28.000
EFG-789 HP XYZ  127687643   …   SerialNumber2       …   2020-10-21 08:35:05.000

Is there any way to acheive that? Many thanks in advance.

What is the unique key in the output table? Is it ResourceID? — CleanBold, Oct 27 '20 at 09:55
using the DISTINCT on BIOSSerialNumber order by LastLogin desc? — Jephren Naicker, Oct 27 '20 at 10:40

score 1 · Accepted Answer · answered Oct 27 '20 at 12:05

Using the row_number function, if you partition by BIOSSerialNumber and order by LastLogin like this:

;with cte_SCCM as
(
    SELECT 
    v_GS_COMPUTER_SYSTEM.Name0 as name,
    v_GS_COMPUTER_SYSTEM_PRODUCT.Version0 as model,
    v_GS_COMPUTER_SYSTEM.ResourceID,
    v_GS_SYSTEM.SystemRole0 as SystemRole,
    v_GS_OPERATING_SYSTEM.Caption0 as caption,
    v_GS_SYSTEM_ENCLOSURE.ChassisTypes0 as chassistype,
    v_GS_WORKSTATION_STATUS.LastHWScan, 
    v_GS_PC_BIOS.SerialNumber0 as BIOSSerialNumber,
    v_GS_COMPUTER_SYSTEM_PRODUCT.UUID0 as UUIDSerialNumber,
    v_GS_SYSTEM_ENCLOSURE.SerialNumber0 as ChassisSerialNumber,
    v_GS_BASEBOARD.SerialNumber0 as BaseboardSerialNumber,
    v_R_SYSTEM.Last_Logon_Timestamp0 as LastLogin,
    ROW_NUMBER() OVER (PARTITION BY v_GS_PC_BIOS.SerialNumber0 ORDER BY v_R_SYSTEM.Last_Logon_Timestamp0 DESC) as RN

    FROM v_GS_COMPUTER_SYSTEM
    LEFT JOIN v_GS_WORKSTATION_STATUS ON v_GS_COMPUTER_SYSTEM.ResourceID = v_GS_WORKSTATION_STATUS.ResourceID 
    LEFT JOIN v_GS_SYSTEM ON v_GS_COMPUTER_SYSTEM.ResourceID = v_GS_SYSTEM.ResourceID 
    LEFT JOIN v_GS_PC_BIOS ON v_GS_COMPUTER_SYSTEM.ResourceID = v_GS_PC_BIOS.ResourceID
    LEFT JOIN v_GS_OPERATING_SYSTEM ON v_GS_COMPUTER_SYSTEM.ResourceID = v_GS_OPERATING_SYSTEM.ResourceID
    LEFT JOIN v_GS_COMPUTER_SYSTEM_PRODUCT ON v_GS_COMPUTER_SYSTEM.ResourceID = v_GS_COMPUTER_SYSTEM_PRODUCT.ResourceID
    LEFT JOIN v_GS_SYSTEM_ENCLOSURE ON v_GS_COMPUTER_SYSTEM.ResourceID = v_GS_SYSTEM_ENCLOSURE.ResourceID
    LEFT JOIN v_GS_BASEBOARD ON v_GS_COMPUTER_SYSTEM.ResourceID = v_GS_BASEBOARD.ResourceID
    LEFT JOIN v_R_SYSTEM ON v_GS_COMPUTER_SYSTEM.ResourceID = v_R_SYSTEM.ResourceID
)

SELECT *
FROM cte_SCCM 
WHERE RN = 1

Thanks a lot, this works perfectly. I was using the ROW_NUMBER() incorrectly, I need to learn more about this function. — Stokres, Oct 27 '20 at 14:36

Query in SQL (SCCM Database) that selects only the newest record when there is a duplicate

1 Answers1