Solved

Upmerge

Posted on 2004-10-17
3
396 Views
Last Modified: 2008-03-17
What is the benifit of using 'upmerge' command introduced in oracle 9i & how it works?
it is my open book bonus question in University i need it's expert answer as soon as possible.
0
Comment
Question by:Fahad_Hafeez
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
3 Comments
 
LVL 6

Accepted Solution

by:
morphman earned 125 total points
ID: 12333446
You mean the MERGE command, or commonly called the "upsert". It is essentially 2 commands in 1, commonly used in ETL transformations. Basically the common operation is

"I want to update existing records, and create new records where a record doesnt already exist".

The merge command providess this functionality in 1 command , MERGE. In 8i SQL you would have to perform 2 statements. An UPDATE followed by an INSERT. This requires 2 table scans as opposed tot he MERGE commands single scan.

Hope this helps,
0

Featured Post

Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Working with Network Access Control Lists in Oracle 11g (part 1) Part 2: http://www.e-e.com/A_9074.html So, you upgraded to a shiny new 11g database and all of a sudden every program that used UTL_MAIL, UTL_SMTP, UTL_TCP, UTL_HTTP or any oth…
Note: this article covers simple compression. Oracle introduced in version 11g release 2 a new feature called Advanced Compression which is not covered here. General principle of Oracle compression Oracle compression is a way of reducing the d…
This video shows, step by step, how to configure Oracle Heterogeneous Services via the Generic Gateway Agent in order to make a connection from an Oracle session and access a remote SQL Server database table.
This video explains what a user managed backup is and shows how to take one, providing a couple of simple example scripts.
Suggested Courses

617 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question