We are now going to look at the Warehouse Builder and its features for designing and building our ETL process. OWB handles this with what are called mappings. A mapping is composed of a series of operators that describe the sources, targets, and a series of operations that flow from source to target to load the data. It is all designed in a graphical manner using the Mapping Editor, which is available from the Design Center. Let's run the Design Center now and take a look at the Mapping Editor, its features, and some of the operators that are available to us. Launch the Design Center as we discussed in Chapter 2 in the Overview of Warehouse Builder Design Center section.
In the Design Center | Project Explorer window, expand the ACME_DW_PROJECT project (if it is not already expanded) by clicking on the plus sign beside it. To access the Mapping Editor, we need a mapping to work on. So to begin with, we can create an empty mapping at this point.