ETL, extract, transform, load, three database functions that are combined into one tool to pull data out of one database and place it into another database.
- Extract is the process of reading data from a database. In this stage, the data is collected, often from multiple and different types of sources.
- Transform is the process of converting the extracted data from its previous form into the form it needs to be in so that it can be placed into another database. Transformation occurs by using rules or lookup tables or by combining the data with other data.
- Load is the process of writing the data into the target database.
Keywords: multi-resources; copy from data sources to data warehouse.
Data extraction involves extracting data from homogeneous or heterogeneous sources; data transformation processes data by data cleansing and transforming them into a proper storage format/structure for the purposes of querying and analysis; finally, data loading describes the insertion of data into the final target database such as an operational data store, a data mart, data lake or a data warehouse.[2][3]
References:
- ERL - Extract, transform, load
