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Chapter 5  Database Processing
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                         Q5-8               2026?


                                            With ever-cheaper data storage and data communications, we can be sure that the volume of
                                            database data will continue to grow, probably exponentially, through 2026. All that data contains
                                            patterns that can be used to conceive information to help businesses and organizations achieve
                                            their strategies. That will make business intelligence, discussed in Chapter 9, even more important.
                                            Furthermore, as databases become bigger and bigger, they’re more attractive as targets for theft or
                                            mischief, as we recently saw at Sony Entertainment. Those risks will make database security even
                                            more important, as we discuss in Chapter 10.
                                               Additionally, the DBMS landscape is changing. While for years relational DBMS products
                                            were the only game in town, the Internet changed that by posing new processing requirements.
                                            As compared  to  traditional database applications, some Internet applications  process many,
                                            many more transactions against much simpler data. A tweet has a much simpler data structure
                                            than the configuration of a Kenworth truck, but there are so many more tweets than truck
                                            configurations!
                                               Also, traditional relational DBMS products devote considerable code and processing power to
                                            support what are termed ACID (atomic, consistent, isolated, durable) transactions. In essence, this
                                            acronym means that either all of a transaction is processed or none of it is (atomic), that  transactions
                                            are processed in the same manner (consistent) whether processed alone or in the presence of millions
                                            of other transactions (isolated), and that once a transaction is stored it never goes away—even in the
                                            presence of failure (durable).
                                               ACID transactions are critical to traditional commercial applications. Even in the presence of
                                            machine failure, Vanguard must process both the sell and the buy sides of a transaction; it cannot
                                            process part of a transaction. Also, what it stores today must be stored tomorrow. But many new
                                            Internet applications don’t need ACID. Who cares if, one time out of 1 million, only half of your
                                            tweet is stored? Or if it’s stored today and disappears tomorrow?
                                               These new requirements have led to three new categories of DBMS:
                                               1. NoSQL DBMS. This acronym is misleading. It really should be NotRelational DBMS. It
                                                  refers to new DBMS products that support very high transaction rates processing relatively
                                                  simple data structures, replicated on many servers in the cloud, without ACID transaction
                                                  support. MongoDB, Cassandra, Bigtable, and Dynamo are NoSQL products
                                               2. NewSQL DBMS. These DBMS products process very high levels of transactions, like the
                                                  NoSQL DBMS, but provide ACID support. They may or may not support the relational
                                                  model. Such products are a hotbed of development with new vendors popping up nearly
                                                  every day. Leading products are yet unknown.
                                               3. In-memory DBMS. This category consists of DBMS products that process databases
                                                  in main memory. This technique has become possible because today’s computer memo-
                                                  ries can be enormous and can hold an entire database at one time, or at least very large
                                                  chunks of it. Usually these products support or extend the relational model. SAP HANA
                                                  is a computer with an in-memory DBMS that provides high volume ACID transaction
                                                  support simultaneously with complex relational query processing. Tableau Software’s
                                                  reporting products are supported by a proprietary in-memory DBMS using an extension
                                                  to SQL.

                                               Does the emergence of these new products mean the death knell for relational databases? It
                                            seems unlikely because organizations have created thousands of traditional relational databases
                                            with millions of lines of application code that process SQL statements against relational data
                                            structures. No organization wants to endure the expense and effort of converting those  databases
                                            and code to something else. There is also a strong social trend among older technologists to
                                            hang onto the relational model. However, these new products are loosening the  stronghold that
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