The data STAGING area is a system that stands between the legacy systems and the analytics system, usually a data warehouse and sometimes an ODS. The data staging area is considered the "back room" portion of the data warehouse ENVIRONMENT. The data staging area is where the extract, transform and LOAD (ETL) takes place and is out of bounds for end users. Some of the functions of the data staging area include:

• Extracting data from multiple legacy systems.
• Cleansing the data, usually with a specialized tool.
• Integrating data from multiple legacy systems into a single data warehouse.
• Transforming legacy system keys into data warehouse keys, usually surrogate keys.
• Transforming disparate codes for gender, marital status, ETC., into the data warehouse standard.
• Transforming the heterogeneous legacy data structures to the data warehouse data structures.
•  Loading the VARIOUS data warehouse tables via automated jobs in a particular sequence through the bulk loader provided with the data warehouse database or a third-party bulk loader.

The data staging area is a system that stands between the legacy systems and the analytics system, usually a data warehouse and sometimes an ODS. The data staging area is considered the "back room" portion of the data warehouse environment. The data staging area is where the extract, transform and load (ETL) takes place and is out of bounds for end users. Some of the functions of the data staging area include: