Below is the scenario,
There is a table called 'test' have data like this
column1 column2 column3
A null 7/14/23
A null 7/15/23
A B 7/16/23
X null 7/14/23
X null 7/15/23
X G 7/16/23
This how data loaded in table 'test'
Now i have to update the records like below (null should be replace with the data which recently loaded)
column1 column2 column3
A B 7/14/23
A B 7/15/23
A B 7/16/23
X G 7/14/23
X G 7/15/23
X G 7/16/23
Please help me how can i update the table records
Note- this table doesn't have any primary key
Im expecting oracle plsql techies to give me idea how can i update records without affecting other dates which loaded correctly
You can use
select column1, first_value(column2) over(partition by column1 order by column3 desc) as column2, column3
from data
as source of the correct data in a MERGE statement. (at condition you can identify uniquely each row...)