![]() ![]() IBM's first commercial relational-database product, SQL/DS, was released for the DOS/VSE and VM/CMS operating systems in 1981. In parallel with the development of SQL, IBM also developed Query by Example (QBE), the first graphical query language. IBM bought Metaphor Computer Systems to utilize their GUI interface and encapsulating SQL platform that had already been in use since the mid-80s. When IBM released its first relational-database product, they wanted to have a commercial-quality sublanguage as well, so it overhauled SEQUEL and renamed the revised language Structured Query Language (SQL) to differentiate it from SEQUEL, and also because the acronym "SEQUEL" was a trademark of the UK-based Hawker Siddeley aircraft company. This led to an inexact interpretation of Codd's relational model that matched only part of the prescriptions of the theory the result was Structured English QUEry Language or SEQUEL. ![]() At the time, IBM didn't believe in the potential of Codd's ideas, leaving the implementation to a group of programmers not under Codd's supervision. To apply the relational model, Codd needed a relational-database language he named DSL/Alpha. A key development of the System R project was the Structured Query Language ( SQL). In 1974, the IBM San Jose Research center developed a relational DBMS, System R, to implement Codd's concepts. Codd, a researcher working for IBM, described the theory of relational databases, and in June 1970 published the model for data manipulation. ĭB2 traces its roots back to the beginning of the 1970s when Edgar F. However, in the 1990s IBM changed track and produced a Db2 common product, designed with a mostly common code base for L-U-W (Linux-Unix-Windows) DB2 for System z and DB2 for IBM i are different. Unlike other database vendors, IBM previously produced a platform-specific Db2 product for each of its major operating systems. The brand name was originally styled as DB/2, then DB2 until 2017 and finally changed to its present form. It initially supported the relational model, but was extended to support object–relational features and non-relational structures like JSON and XML. Db2 is a family of data management products, including database servers, developed by IBM. ![]()
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