In this chapter, you have been getting data from different kinds of sources. In all cases, the source of the data was unique; for example, a plain file or the result of a single query. However, what if we had more than one source, and we wanted to combine them and use them as a single dataset? In this section, you will learn how to deal with this very common situation.
Combining different sources into a single dataset
Manipulating the metadata
Let's look at the first exercise again, where we read a file containing surveys. On that occasion, we read all of the information in the file. Now, suppose that we are interested in just a few fields: room_id, room_type, neighborhood, overall_satisfaction, accommodates...