Relational database management system ( RDBMS ), less often - relational database management system ( RDBMS ) - DBMS that manages relational databases .
Virtually all developers of modern applications that provide communication with database systems are oriented towards relational DBMS  . According to analysts for 2010, relational database management systems are used in the vast majority of large-scale projects for the development of information systems . According to the research results of IDC 2009, only about 7% are projects that use non-relational DBMS  .
According to Gartner, in 2013, the relational database system was $ 26 billion with an annual increase of about 9 percent, and by 2018, the relational database system will reach $ 40 billion  . Currently, the absolute leaders of the DBMS market are Oracle , IBM and Microsoft , with a total aggregate market share of about 90%, supplying systems such as Oracle Database , IBM DB2 and Microsoft SQL Server  .
The only commercially successful DBMS of Russian origin is the relational DBMS Linter  .
In 1974, IBM started a research project for developing RDBMS, called System R  . Its first commercial product was IBM SQL / DS, released in 1982  .
However, the first commercially successful RDBMS was Oracle, released in 1979 by Relational Software, which was later renamed Oracle Corporation  .
In the 1970s, when almost all the main theoretical results were obtained and even the first prototypes of relational DBMS existed, many authoritative experts denied the possibility of achieving effective implementation of such systems. However, the advantages of the relational approach and the development of methods and algorithms for organizing and managing relational databases have led to the fact that by the end of the 1980s, relational systems occupied a dominant position in the global DBMS market. 
Due to the sharp increase in the popularity of RDBMS in the 1980s, many companies began to position their DBMS as “relational” for advertising purposes, sometimes not having sufficient grounds for this, as a result of which the author of the relational data model Edgar Codd published his famous “ 12 Codd Rules ”which each RDBMS must satisfy.
- Fowler, Martin . Architecture of corporate software applications.: Per. from English - M .: Publishing house "Williams", 2007. - 544 p.: Ill.
- Maxim Nikitin. Is the era of relational DBMS over? // CNews.ru, 2010
- The future of these enterprises: relational DBMS will survive // Think Innovative, 2013
- Protected Relational DBMS Linter // Open Systems, No. 11-12, 1999
- Funding a Revolution: Government Support for Computing Research. - National Academies Press, Jan. 8, 1999. - “System R didn’t convince IBM management to abandon its existing product”. - ISBN 0309062780 .
- Hershel Harris, Bert Nicol. SQL / DS: IBM's First RDBMS // IEEE Annals of the History of Computing, Volume 35, Number 2, April – June 2013, pp. 69-71
- Oracle Timeline (Undefined) // Profit Magazine. - Oracle, 2007. - May ( Vol. 12 , No. 2 ). - p . 26 .
- Kuznetsov, S. D., 2007 .
- K.J. Date. Introduction to Database Systems = Introduction to Database Systems. - 8th ed. - M .: Williams , 2006. - p. 1328. - ISBN 0-321-19784-4 .
- Kuznetsov SD Basics of databases. - 2nd ed. - M .: Internet University of Information Technology; BINOMIAL. Laboratory of Knowledge, 2007. - 484 p. - ISBN 978-5-94774-736-2 .