We had our first introduction to the process of ETL in the last chapter where we discussed what it is and saw the features the Warehouse Builder has for designing our ETL processes. We looked at the Mapping Editor, which is the main interface we'll use to build our ETL mappings. We also looked at the objects in OWB that we can use. However, we didn't get to do anything other than just look. We have all this new knowledge and are ready to use it. So let's work on designing a mapping, which will make use of some of the features we looked at in the last chapter.