According
to Wikipedia, A relational database is
a collection of data items organized as a set of formally described tables from
which data can be accessed easily. The software used in a relational database is called a relational database management system (RDBMS). A relational database is the
predominant choice in storing data, over other models like the hierarchical
database model or the network model. It consists of n number tables and each
table has its own primary key. The standard user and application program interface to a
relational database is the structured query language (SQL). SQL statements are used
both for interactive queries for information from a relational database and for
gathering data for reports.
The relational database was first defined in June 1970 by Edgar Codd, of IBM's San Jose
Research Laboratory. Codd called his paper, “A Relational Model of Data for Large
Shared Data Banks.” What Codd did was open
the door to a new world of data independence. Users wouldn’t have to be
specialists, nor would they need to know where the information was or how the
computer retrieved it. They could now concentrate more on their businesses and
less on their computers.
The
example posted by Gabrielle Carpenter is a good way to
understand relational database. A relational database allows you to easily find
specific information. It also allows you to sort based on any field and
generate reports that contain only certain fields from each record. Relational
databases use tables to store information. The standard
fields and records are represented as columns (fields) and rows (records) in a
table. I think
the major reasons for the success of the relational model were the high degree
of logical independence and it allows a natural and expressive representation
based on tables. Today, the ease and flexibility of relational databases have made them the
predominant choice for financial records, manufacturing and logistical
information, and personnel data. Most routine data transactions—accessing bank
accounts, using credit cards, trading stocks, making travel reservations,
buying things online—all use structures based on relational database theory.
Hugh
Darwen: An introduction to relational database theory
"What
Are Relational Databases?" HowStuffWorks. http://computer.howstuffworks.com/question599.htm
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