Summary

Learning outcomes

In this chapter, we learned how to add a new column to an existing table. We also learned how powerful indexes are and how to create them. We went over how to verify whether an index has been created and looked at which part of the table structure definition denotes the presence of an index. We learned how to remove an index and how we can verify that the index has been removed. Finally, we learned what response we get when we try to violate the rules of a unique index.