A database server is a server which uses a
database application
A database application is a computer program whose primary purpose is retrieving information from a computerized database. From here, information can be inserted, modified or deleted which is subsequently conveyed back into the database. Early e ...
that provides
database
In computing, a database is an organized collection of data stored and accessed electronically. Small databases can be stored on a file system, while large databases are hosted on computer clusters or cloud storage. The design of databases s ...
services to other computer programs or to
computers, as defined by the
client–server model
A model is an informative representation of an object, person or system. The term originally denoted the plans of a building in late 16th-century English, and derived via French and Italian ultimately from Latin ''modulus'', a measure.
Models c ...
.
Database management systems
In computing, a database is an organized collection of data stored and accessed electronically. Small databases can be stored on a file system, while large databases are hosted on computer clusters or cloud storage. The design of databases spa ...
(DBMSs) frequently provide database-server functionality, and some database management systems (such as
MySQL
MySQL () is an open-source relational database management system (RDBMS). Its name is a combination of "My", the name of co-founder Michael Widenius's daughter My, and "SQL", the acronym for Structured Query Language. A relational database ...
) rely exclusively on the client–server model for database access (while others, like
SQLite
SQLite (, ) is a database engine written in the C programming language. It is not a standalone app; rather, it is a library that software developers embed in their apps. As such, it belongs to the family of embedded databases. It is the m ...
, are meant for use as an
embedded database
An embedded database system is a database management system (DBMS) which is tightly integrated with an application software; it is embedded in the application. It is a broad technology category that includes:
* database systems with differing ...
).
Users access a database server either through a "
front end" running on the user's computerwhich displays requested dataor through the "
back end", which runs on the server and handles tasks such as data analysis and storage.
In a
master-slave model, database master servers are central and primary locations of data while database slave servers are synchronized backups of the master acting as
proxies.
Most database applications respond to a
query language
Query languages, data query languages or database query languages (DQL) are computer languages used to make queries in databases and information systems. A well known example is the Structured Query Language (SQL).
Types
Broadly, query language ...
. Each database understands its query language and converts each submitted query to server-readable form and executes it to retrieve results.
Examples of proprietary database applications include
Oracle,
IBM Db2,
Informix
IBM Informix is a product family within IBM's Information Management division that is centered on several relational database management system (RDBMS) offerings. The Informix products were originally developed by Informix Corporation, whose ...
, and
Microsoft SQL Server
Microsoft SQL Server is a relational database management system developed by Microsoft. As a database server, it is a software product with the primary function of storing and retrieving data as requested by other software applications—which ...
. Examples of
free software
Free software or libre software is computer software distributed under terms that allow users to run the software for any purpose as well as to study, change, and distribute it and any adapted versions. Free software is a matter of liberty, no ...
database applications include
PostgreSQL; and under the
GNU General Public Licence
The GNU General Public License (GNU GPL or simply GPL) is a series of widely used free software licenses that guarantee end users the four freedoms to run, study, share, and modify the software. The license was the first copyleft for general u ...
include
Ingres and
MySQL
MySQL () is an open-source relational database management system (RDBMS). Its name is a combination of "My", the name of co-founder Michael Widenius's daughter My, and "SQL", the acronym for Structured Query Language. A relational database ...
. Every server uses its own query logic and structure. The
SQL (Structured Query Language) query language is more or less the same on all
relational database applications.
For clarification, a database server is simply a server that maintains services related to clients via database applications.
DB-Engines lists over 300 DBMSs in its ranking.
History
The foundations for modeling large sets of data were first introduced by
Charles Bachman
Charles William Bachman III (December 11, 1924 – July 13, 2017) was an American computer scientist, who spent his entire career as an industrial researcher, developer, and manager rather than in academia. He was particularly known for his ...
in 1969.
Bachman introduced
Data Structure Diagrams (DSDs) as a means to graphically represent data. DSDs provided a means to represent the relationships between different data entities. In 1970,
Codd introduced the concept that users of a database should be ignorant of the "inner workings" of the database.
Codd proposed the "relational view" of data which later evolved into the
Relational Model which most databases use today. In 1971, the Database Task Report Group of
CODASYL
CODASYL, the Conference/Committee on Data Systems Languages, was a consortium formed in 1959 to guide the development of a standard programming language that could be used on many computers. This effort led to the development of the programming l ...
(the driving force behind the development of the programming language
COBOL) first proposed a "data description language for describing a database, a data description language for describing that part of the data base known to a program, and a data manipulation language."
Most of the research and development of databases focused on the relational model during the 1970s.
In 1975 Bachman demonstrated how the relational model and the data structure set were similar and "congruent" ways of structuring data while working for
Honeywell
Honeywell International Inc. is an American publicly traded, multinational conglomerate corporation headquartered in Charlotte, North Carolina. It primarily operates in four areas of business: aerospace, building technologies, performance ma ...
.
The
Entity-relationship model was first proposed in its current form by
Peter Chen
Peter Pin-Shan Chen (; born 3 January 1947) is a Taiwanese American computer scientist. He is a (retired) distinguished career scientist and faculty member at Carnegie Mellon University and Distinguished Chair Professor Emeritus at LSU. He is ...
in 1976 while he was conducting research at
MIT
The Massachusetts Institute of Technology (MIT) is a private land-grant research university in Cambridge, Massachusetts. Established in 1861, MIT has played a key role in the development of modern technology and science, and is one of the m ...
.
The Entity-Relationship Model: Toward a Unified View of Data (1976)
/ref> This model became the most frequently used model to describe relational databases. Chen was able to propose a model that was superior to the navigational model and was more applicable to the "real world" than the relational model proposed by Codd.
See also
* Database replication
Replication in computing involves sharing information so as to ensure consistency between redundant resources, such as software or hardware components, to improve reliability, fault-tolerance, or accessibility.
Terminology
Replication in comp ...
References
{{Database
Data management
Servers (computing)