Hi,
I am preparing for my data architect certification and while doing sample questions I came across the following question.
Q) A data architect needs to load large amounts of data from a database which is continuously updated New records are added, and existing records get updated and deleted. Each record has a LastModified field All existing records are exported into a QVD file. The data architect wants to load the records into Qlik Sense efficiently.
Which steps should the data architect take to meet these requirements?
A.
1. Load the new and updated data from the database
2. Load the existing data from the QVD without the updated rows that have just been loaded from the database. Concatenate with the new and updated records.
3. Load all records from the key field from the database and use an Inner Join on the previous table.
B.
1. Load the existing data from the QV
2. Load new and updated data from the database. Concatenate with the table loaded from the QVD.
3. Create a separate table for the deleted rows and use a WHERE NOT EXISTS to remove these records.
C.
1. Load the existing data from the QVD.
2. Load the new and updated data from the database without the rows that have just been loaded from the QVD. Concatenate with data from the QVD.
3. Load all records from the key field from the database and use an Inner Join on the previous table.
D. (Right Answer)
1. Use a partial load to load new and updated data from the database.
2. Load the existing data from the QVD without the updated rows that have just been loaded from
the database. Concatenate with the new and updated records.
3. Use the Peek function to remove the deleted rows.
My doubt is..
If D is the right answer..how is Peek function used to remove the deleted rows?
To remove deleted rows in the incremental load process we usually use inner join. right! which makes 'C' the right answer.
Please help.
Thanks,
Sai
