What is ETL or Extract, Transform, and Load?

An article by Jorge Reis    Comments Off on What is ETL or Extract, Transform, and Load?

To be able to understand ETL better, it’s best to first briefly say what a data warehouse is.  When you talk about Data Warehouse, what you’re actually talking about is the place where you keep all your data – electronically, that is.  However, your data warehouse isn’t only the place where you store all the electronic data you’ve gathered and now want to keep for future use.  It’s not like a garage where you carelessly throw in everything you’ve gathered.  Your data warehouse should be designed in such a way that your data collecting and storing are well-organized.  This will ensure that your basic data management system is as effective as can be; otherwise, your business will be sorely affected by a mismanaged data storage system.

Data Warehousing and ETL

ETL is the abbreviation for Extract, Transform and Load – processes that you use in data warehousing.  ETL ensures that your electronic data will reach its destination – your data warehouse – intact and in good condition, efficiently and effectively.

First on the list is Extract.  Extracting data means that you are getting the data from its source, and these sources may be different from one another with different formats.  Therefore, it is very important that your extracting process is efficient as it is also in this process that your data that have been extracted will be converted to the appropriate format to make it ready for the next process, which is transforming of the data.

Transforming the data may require different processes, depending on the kind of data that you have extracted.  This transformation of data means that your extracted data will be manipulated in a way that will prepare it for the next process which is loading.  As mentioned, the transformation process may vary, depending on the kind of extracted data that needs to be loaded to the database or the data warehouse.  Others need very little modification, while others require several steps.

The final stage is the loading.  Here is where all the extracted and then transformed data are finally loaded into your data warehouse or you database for storage.

ETL Software/Tools

To be able to run your ETL processes, you will be needing the appropriate ETL software.  This means that your ETL software should be able to do all three processes on your data to make them compatible enough to be stored in your databases or your data warehouse.

Your ETL software should be able to Extract, Transform and Load data derived from any source to its destination for storage.  ETL being a vital factor in your data management, one must not overlook the kind of ETL software or tools that you will be using.

While ETL tools could prove to be costly, it is nonetheless important to note that its importance cannot be emphasized enough.  This is why your choice of ETL tools is likewise very important.  It should be able to provide you with all the appropriate ETL processes for the completion of your data migration to ensure that your database will always be accurate, up-to-date and efficient.