ETL

The process of extracting, transforming, and loading data can appear rather complicated. We do have a special term to describe it, ETL, which contains the three steps mentioned. We're dealing with source data on different database systems from our target and a database from a vendor other than Oracle. Let's look from a high level at what is involved in getting that data from a source system to our target, and then take a look at whether to stage the data or not. We will then see how to automate that process in Warehouse Builder, which will relieve us of much of the work.

Manual ETL processes

First of all, we need to be able to get data out of that source system and move it over to the target system. We can't begin to do anything until that is accomplished, but what means can we use to do so? We know that the Oracle Database provides various methods to load data into it. There is an application that Oracle provides called SQL*Loader, which is a utility to load data from flat files. This...