Oracle 18c

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create table STPDLV_ENTRY_TABLE (STP_UDF9 varchar(50)
                                 , DLV_FLOW_XX int
                                 , TS_TIME_LONG int)
insert into STPDLV_ENTRY_TABLE values ('bla', 3741539, 1)
1 rows affected

insert into STPDLV_ENTRY_TABLE values ('bla', 4044126, 2)
1 rows affected

insert into STPDLV_ENTRY_TABLE values ('bla', 5555555, 3)
1 rows affected

update (select * 
from STPDLV_ENTRY_TABLE a 
inner join (select DLV_FLOW_XX
                   , max(TS_TIME_LONG) AS MaxDateTime 
            from STPDLV_ENTRY_TABLE 
            group by DLV_FLOW_XX) b 
on a.DLV_FLOW_XX = b.DLV_FLOW_XX
and a.TS_TIME_LONG = b.MaxDateTime
and a.DLV_FLOW_XX in (3741539,4044126,3741551)
and a.STP_UDF9 !='Posted') Test
set test.STP_UDF9 = 'Posted';
2 rows affected

select * from STPDLV_ENTRY_TABLE;


STP_UDF9
DLV_FLOW_XX
TS_TIME_LONG


Posted
3741539
1

Posted
4044126
2

bla
5555555
3