From the course: Advanced SQL for Data Scientists
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Denormalization
- [Presenter] Now sometimes we choose to denormalize our data because denormalization can give us significantly better performance. So let's take a look at some of the characteristics of denormalized tables. Well, data is often redundant. So for example here in this example, looking at a book's table, we have author information that's duplicated as well as publisher information. We may have non-atomic values. So for example, some analytical databases allow and actually encourage the use of strokes or structures to have more complex values within a column than simple atomic values and then we also tolerate transitive dependencies. So if we have say a value that's dependent solely on a non-key attribute in the table and that non-key attribute is itself dependent on the primary key. That's totally fine. Again, it violates the third normal form but we're willing to tolerate that because in exchange for not being…
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