-
Before the introduction of DBMS, all data were stored in individual files.
The issue was it was a huge problem to maintain
Idea was to take the definition of a file’s content and structure out of individual programs, and store it together with the data in a database -
-
IBM developed the Generalized Update Access Method (GUAM) in 1964 for North American Rockwell, the prime contractor for the APOLLO project
-
In the mid-1960s, General Electric developed Integrated Data Store (I-D-S)
-
GUAM was made available for the general public under the name Data Language/I (DL/I) in 1966. This became the data management component for the Information Management System (IMS), which was the dominant DBMS for many years
-
The COnference on DAta SYstems Languages (CODASYL) tackled the problem of providing standards for DBMSs in the late 1960s
-
1970 E.F. (Ted) Codd published landmark paper in which he applied concepts from relational algebra to problems of storing large amounts of data
Throughout the 1970s, the relational model was the subject of intense research
Initially there was a lot of resistance to the relational model -
In 1971, the CODASYL standards were presented to the American National Standards Institute (ANSI)
-
Codd’s article triggered a flurry of relational database research, including a major research project in IBM.
Goal of the project, called System /R, was to prove the workability of the relational concept and to provide some experience in actually implementing a relational DBMS.
Work began in the mid 1970s. -
In 1974 & 1975, the first phase of System /R produced a minimal prototype.
In addition, the project included work on database query languages. One of these languages was called SEQUEL, an acronym for Structured English Query Language. -
University of California, Berkeley also researched relational databases in the mid-1970s.
Developed Ingres
Had a query language called QUEL. -
Publicity about System /R attracted the attention of a group of engineers in Menlo Park, California.
Saw a chance for a commercial product.
In 1977 formed a company called Relational Software to build a relational DBMS based on SQL.
Named their product “Oracle”. -
In 1978 & 1979 implemented System /R in some client sites. Also implement the query language which changed to SQL (Structured Query Language) for legal reasons.
Despite the name change, the SEQUEL pronunciation remained -
Relational Software ships Oracle it in 1979 and it was the first commercially available relational DBMS.
Beat IBM’s first product to market by a full 2 years.
Aggressively sold their product and eventually renamed the company after its flagship. -
In 1980, several professors left Berkeley and founded Relational Technology, Inc which built a commercial version of Ingres.
Ingres and Oracle were arch-rivals.
Although Ingres was technologically superior in many areas, lost out to Oracle’s aggressive marketing. -
Meanwhile, IBM was turning System /R into a commercial product called SQL/DS.
Began shipping in 1982. -
In 1983, IBM introduced Database 2 (DB2). Shipped this in 1985.
-
By May 1985, Oracle claimed to have over 1000 installations, Ingres claimed a similar number and SQL/DS plus DB2 also around 1000.
-
Still a struggle against traditional databases, but query languages (e.g. SQL, QUEL) pushed them forward.
Market forces boosted popularity of SQL in the late 1980s.
Through early 1990s, steadily improving SQL implementations and dramatic improvements in processor speeds made SQL a practical solution for transaction processing applications. -
SQL’s supremacy in the database world has not gone unchallenged.
Early 1990s “object databases” look as though they will take over as did object-oriented programming.
Lots of venture capital-backed “object database” companies.
hoped to make relational databases and their vendors obsolete.
SQL and relational databases so far have more than withstood the challenge. -
Total revenues for object-oriented databases are measured in hundreds of millions of dollars (at best).
Total revenues for SQL and relational DBMS tools & services are measured in tens of billions of dollars of sales per year.
