Editing IBM System R (section)

{{short description|Relational database management system, first implementation of SQL}}
'''IBM System R''' is a [[database]] system built as a research project at [[IBM]]'s [[IBM Almaden Research Center|San Jose Research Laboratory]] beginning in 1974,<ref>
{{cite web
|url=http://www.cs.berkeley.edu/~brewer/cs262/SystemR.pdf
|title=A History and Evaluation of System R
|publisher=IBM
|quote="Phase Zero" of the project, which occurred during 1974 and-most of 1975, involved the development of the SQL user interface}}</ref> led by [[Edgar Codd]], to implement his ideas on [[relational database]]s.<ref name="rdbmsearlyyearsoh20070612">{{Cite interview |interviewer=Burton Grad |title=RDBMS Plenary 1: Early Years |url=https://archive.computerhistory.org/resources/access/text/2013/05/102702562-05-01-acc.pdf |access-date=2025-05-30 |publisher=Computer History Museum |date=2007-06-12}}</ref> System R was a [[:wikt:seminal|seminal]] project as the first implementation of [[SQL]], which has since become the standard [[relational model|relational]] data [[query language]]. It was also the first system to demonstrate that a relational database could provide good [[transaction processing]] performance. Design decisions in System R, as well as some fundamental [[algorithm]] choices (such as the [[dynamic programming]] algorithm used in [[query optimization]]<ref>{{citation
    | first1 = PG | last1 = Selinger | author1-link = Patricia Selinger
    | first2 = MM | last2 = Astrahan
    | first3 = Donald D | last3 = Chamberlin | author3-link = Donald D. Chamberlin
    | first4 = RA | last4 = Lorie
    | first5 = TG | last5 = Price
    | year = 1979 | pages = 23–34 | contribution = Access Path Selection in a Relational Database Management System | doi = 10.1145/582095.582099
    | title = Proceedings of the 1979 ACM SIGMOD International Conference on Management of Data| isbn = 978-0897910019 | s2cid = 8537523 }}</ref>), influenced many later relational systems.

System R's first customer was [[Pratt & Whitney]] in 1977.<ref>{{Citation | url = http://www.mcjones.org/System_R/SQL_Reunion_95/sqlr95-System.html | last = McJones | first = P | title = System R | contribution = SQL reunion | year = 1995}}.</ref> Not running on [[Unix]] hurt its popularity.{{r|rdbmsearlyyearsoh20070612}}