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Carl Reynolds and Paul Tymann

"Schaum's Outline of Principles of Computer Science"


139
Codd also proposed a language for data access that was based on set theory (in the 1980s IBM would bring
structured query language (SQL) to the world). To many professionals at the time, Codd??™s proposals seemed
impossible to implement efficiently.
However, in the 1980s, Oracle became the first company to offer a commercial implementation of a relational
database, and IBM began selling its relational database called DB2. Today the relational data model is
predominant, and that is the model on which this chapter will focus.
With the advent of object-oriented programming, new data management designs called object-relational or
object-oriented database management have been developed. These systems promise convenience and congruity
of operation with OO programming techniques. While they have not yet become widely successful, they may
become so in the future.
ADVANTAGES OF USING A DATABASE
The primary motivation for using a database is speed of access. Assuming proper database design, access
to individual pieces of information can be essentially instantaneous, regardless of the number of data records
or the size of the database. The experience of instantaneously finding exactly the record in which you are
interested, from among millions, can be a stunning one.


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