The TRANS_SUMMARY table contains product-wise transaction details that get updated with every
transaction in the system. Each row has cumulative transaction details of a single product and every
product is identified by a product code, which is the primary key.As part of the archival process, the
company wants to transfer the rows in the TRANS_SUMMARY table to the TRANS_SUMMARY_DUP
table at the end of every quarter of the year. Along with existing products, the company deals with
many new products during every quarter. Which method is best suited for this quarterly data
transfer?
A.
Using the MERGE command
B.
Using the SQL*Loader utility
C.
Using the correlated UPDATE command
D.
Using the INSERT command to perform bulk operation
TRANS_SUMMARY table contains product-wise details of the transaction, so that each time the transaction operation will be updated in the system. Each line of each single product has accumulated transaction detail, every product code marks each product, product code as the primary key.
As part of the archiving process, the company hopes at the end of each quarter, we put these lines in TRANS_SUMMARY transferred to TRANS_SUMMARY_DUP table, in every quarter the company deal with a lot of new products, together with the already existing product processed together.
The MERGE command performs UPDATE and INSERT in one command. You can merge data from one source to another source, and thus choose to insert a new row and update a specific column (if the line already exists).
This question is meant to merge the data in to TRANS_SUMMARY_DUP TRANS_SUMMARY table, if there exists TRANS_SUMMARY_DUP product is retained, if a new product is inserted.