Extract, Transform, Load (ETL) combines three data processing functions that transfer data from a data source to a target database.
The first stage, Extract, involves reading and extracting data from various source systems.
The second stage, Transform, converts the data from its original format into the format that meets the requirements of the target database.
The last stage, Load, saves the new data into the target database, thus finishing the process of transferring the data.
Extract
During the Extract stage, data is extracted from one of the data sources in the ETL Source panel.
Transform
During the Transform stage, the extracted data is transformed to a single table can be loaded to a table shown in the ETL Object panel.
The transformation logic is shown in the ETL SQL Statement panel associated with the target table currently selected in the ETL Object panel.
Load
During the Load stage, the data that was extracted and transformed is loaded to the target table associate with the SQL statement shown in the ETL SQL Statement panel.
The load operation can write, change or delete data in the target table depending on the Load Type selected in the ETL SQL Statement panel.
Extract-Transform-Load mechanisms, available with ETL+, combine the data integration tasks of:
Extracting data from a source database
Transforming it, and
Loading the transformed data into a target database
Scheduling ETL tasks to run on a regular basis.
Displaying log files from previous runs.