ETL

Definition
====ETL - Extract - Transform- Load. Combination of different functions needed to analyse data in a network of databases. According to the CASE study, ETL is a solution that ASI in Mexico wants to implement in order to increase their efficiency.====

1. "Extract" function reads the data from a particular source/database and extracts a certain data subset.
figure 2 for instance, expiry dates of a particular product in a store.

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2. "Transform" function processes the acquired data - using rules, relationships, queries, combining different types of data - to convert extracted data to the form needed for analysis and reporting by Data Warehouses. For instance, data warehouse transforms the expiry dates from American standard (showed on the figure) to British standard, changing month and date placements. This is data transformation for another database, which is managed by British analysts. =====

3. "load" function is used to write the resulting data to a target database. It's the final stage of ETL. (Oracle, n.d.)
 figure 3. (cited in Bibliography)

Oracle Warehouse Builder! The video below outlines how the Oracle Warehouse Builder works, using ETL tools.
media type="youtube" key="WOo6VQ89JzM" width="560" height="315"

Contributor: Ermek
It is most commonly used for big data warehouses, where data needs to be loaded regularly. This processing allows for big companies to be able to be more systemized and mroe organized in their data storing. Moreover ETL allows for so to say "visual flow" where the logic of the system can be observed visually.

Resources

 * figure 1, figure 2, figure 3. Difference between ETL tools and OLAP. (n.d.) Retrieved on December 3, 2014 from < [|demofield.blogspot.com]>
 * Oracle Warehouse Builder. Retrieved on December 3, 2014 from < @http://youtu.be/WOo6VQ89JzM >
 * Overview of Extraction, Transformation. (n.d.) Retrieved on December 3, 2014 from 
 * Rouse, M. extract-transform-load (ETL).(n.d.) Retrieved on December 2, 2014 from 
 * The 7 biggest benefits of ETL tools. (2014, July 24). Retrieved December 10, 2014, from http://www.etltool.com/the-7-biggest-benefits-of-etl-tools/
 * The 7 biggest benefits of ETL tools. (2014, July 24). Retrieved December 10, 2014, from http://www.etltool.com/the-7-biggest-benefits-of-etl-tools/