Why database management systems?
• Database management systems (DBMSs) are very good at organizing and managing large collections of persistent data. • We use DBMSs to help cope with large amounts of data because, when problems get big, they get hard. • Consider the task of finding a particular book in a typical university library. • Now, reconsider that same task if the library doesnt keep the books arranged in any particular order or if the library has no indexes. • Using a big collection of unorganized things is practically impossible. Structure turns data into information. • Persistence means that the data exist permanently; they do not disappear when the computer is shut off. • DBMSs are like suitcases: they are somewhere to put stuff so that its all in one place and easy to get to. • DBMSs help protect data from unauthorized access. • DBMSs help protect data from accidental corruption or loss due to: • hardware failures such as power outages and computer crashes • software failures such as operating system crash
