Computer in Use. Маркушевская Л.П - 95 стр.

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Университет ИТМО | Санкт-Петербург

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95
The first database management systems were developed in the 1960s. A
pioneer in the field was Charles Bachman. Bachman's early papers show that his aim
was to make more effective use of the new direct access storage devices becoming
available: until then, data processing had been based on punched cards and magnetic
tape, so that serial processing was the dominant activity. Two key data models arose
at this time: CODASYL developed the network model based on Bachman's ideas,
and (apparently independently) the hierarchical model was used in a system
developed by North American Rockwell, later adopted by IBM as the cornerstone of
their IBM product. The relational model was proposed by E. F. Codd in 1970. The
first successful database product for microcomputers was dBASE for the CP/M and
PC-DOS/MS-DOS operating systems.
During the 1980s, research activity focused on distributed database systems and
database machines, but these developments had little effect on the market.
In the 1990s, attention shifted to object-oriented databases. These had some
success in fields where it was necessary to handle more complex data than relational
systems could easily cope with, such as spatial databases, engineering data (including
software engineering repositories), and multimedia data. Some of these ideas were
adopted by the relational vendors, who integrated new features into their products as
a result.
In the 2000s, the fashionable area for innovation is the XML database. As with
object databases, this has spawned a new collection of startup companies, but at the
same time the key ideas are being integrated into the established relational products.
XML databases aim to remove the traditional divide between documents and data,
allowing all of an organization's information resources to be held in one place,
whether they are highly structured or not.
Task 1. Write the summary of the text (about 6 lines).
Task 2. Write out main terms from the text and give explanation in English.

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