ETL (Extract Transform Load) jobs extract data from the Data Warehouse
and populate one or more Data Marts for use by groups of decision makers in
the organizations. The Data Marts can be Dimensional (Star Schemas) or
relational, depending on how the information is to be used and what "front
end" Data Warehousing Tools will be used to present the information.
Each Data Mart can contain different combinations of tables, columns and
rows from the Enterprise Data Warehouse. For example, an business unit
or user group that doesn't require a lot of historical data might only need
transactions from the current calendar year in the database. The Personnel
Department might need to see all details about employees, whereas data such
as "salary" or "home address" might not be appropriate for a Data Mart that
focuses on Sales.
