Chapter 7. Expanding Your Data Model
In the preceding chapters, we focused largely on the high-level structure of Cassandra tables, and particularly on the forms and uses of primary keys. Now, we will turn our focus to the data that's stored within tables, exploring advanced techniques to add, change, and remove data.
We created several tables in the MyStatus application, but so far we haven't made any changes to those tables' schemas. In this chapter, we'll introduce the ALTER TABLE
statement, which enables us to add and remove columns from the tables in our keyspace.
We'll move on to the UPDATE
statement, which is used to change the data in existing rows. You'll learn that INSERT
and UPDATE
have more in common than our experience with relational databases might lead us to believe, and that INSERT
in particular can have unexpected and undesirable effects if not used carefully. We'll also expand our understanding of the DELETE
statement, using...