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Network Model
In computing, the network model is a database model conceived as a flexible way of representing objects and their relationships. Its distinguishing feature is that the schema, viewed as a graph in which object types are nodes and relationship types are arcs, is not restricted to being a hierarchy or lattice. The network model was adopted by the CODASYL Data Base Task Group in 1969 and underwent a major update in 1971. It is sometimes known as the CODASYL model for this reason. A number of network database systems became popular on mainframe and minicomputers through the 1970s before being widely replaced by relational databases in the 1980s. Overview While the hierarchical database model structures data as a tree of records, with each record having one parent record and many children, the network model allows each record to have multiple parent and child records, forming a generalized graph structure. This property applies at two levels: the schema is a generalized graph of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bachman Order Processing Model
Bachman may refer to: * Bachman (surname) * Bachman, Ohio * Bachman, West Virginia * Bachman Khan (1210–1239 or 1240), a Kimak khan *Bachmann knot The Bachmann hitch (sometimes misspelled 'Bachman') is a friction hitch, named after the Austrian alpinist Franz Bachmann. It is useful when the friction hitch needs to be reset quickly or often or made to be self-tending as in crevasse and sel ..., often used in mountaineering for ascending on ropes * Bachman Station, a train station on the Dallas Area Rapid Transit Green and Orange Lines See also * * * Bachmann * Backman {{disambiguation, geo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Relational Model
The relational model (RM) is an approach to managing data using a structure and language consistent with first-order predicate logic, first described in 1969 by English computer scientist Edgar F. Codd, where all data are represented in terms of tuples, grouped into relations. A database organized in terms of the relational model is a relational database. The purpose of the relational model is to provide a declarative method for specifying data and queries: users directly state what information the database contains and what information they want from it, and let the database management system software take care of describing data structures for storing the data and retrieval procedures for answering queries. Most relational databases use the SQL data definition and query language; these systems implement what can be regarded as an engineering approximation to the relational model. A '' table'' in a SQL database schema corresponds to a predicate variable; the contents of a tab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graph Database
A graph database (GDB) is a database that uses graph structures for semantic queries with nodes, edges, and properties to represent and store data. A key concept of the system is the graph (or edge or relationship). The graph relates the data items in the store to a collection of nodes and edges, the edges representing the relationships between the nodes. The relationships allow data in the store to be linked together directly and, in many cases, retrieved with one operation. Graph databases hold the relationships between data as a priority. Querying relationships is fast because they are perpetually stored in the database. Relationships can be intuitively visualized using graph databases, making them useful for heavily inter-connected data. Graph databases are commonly referred to as a NoSQL database. Graph databases are similar to 1970s network model databases in that both represent general graphs, but network-model databases operate at a lower level of abstraction and lac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Equipment Corporation
Digital Equipment Corporation (DEC ), using the trademark Digital, was a major American company in the computer industry from the 1960s to the 1990s. The company was co-founded by Ken Olsen and Harlan Anderson in 1957. Olsen was president until he was forced to resign in 1992, after the company had gone into precipitous decline. The company produced many different product lines over its history. It is best known for the work in the minicomputer market starting in the early 1960s. The company produced a series of machines known as the Programmed Data Processor, PDP line, with the PDP-8 and PDP-11 being among the most successful minis in history. Their success was only surpassed by another DEC product, the late-1970s VAX "supermini" systems that were designed to replace the PDP-11. Although a number of competitors had successfully competed with Digital through the 1970s, the VAX cemented the company's place as a leading vendor in the computer space. As microcomputers improved in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OpenVMS
OpenVMS, often referred to as just VMS, is a multi-user, multiprocessing and virtual memory-based operating system. It is designed to support time-sharing, batch processing, transaction processing and workstation applications. Customers using OpenVMS include banks and financial services, hospitals and healthcare, telecommunications operators, network information services, and industrial manufacturers. During the 1990s and 2000s, there were approximately half a million VMS systems in operation worldwide. It was first announced by Digital Equipment Corporation (DEC) as VAX/VMS (''Virtual Address eXtension/Virtual Memory System'') alongside the VAX-11/780 minicomputer in 1977. OpenVMS has subsequently been ported to run on DEC Alpha systems, the Itanium-based HPE Integrity Servers, and select x86-64 hardware and hypervisors. Since 2014, OpenVMS is developed and supported by VMS Software Inc. (VSI). OpenVMS offers high availability through computer cluster, clustering—the ability t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oracle Corporation
Oracle Corporation is an American Multinational corporation, multinational computer technology company headquartered in Austin, Texas. Co-founded in 1977 in Santa Clara, California, by Larry Ellison, who remains executive chairman, Oracle was the List of the largest software companies, third-largest software company in the world in 2020 by revenue and market capitalization. The company's 2023 ranking in the Forbes Global 2000, ''Forbes'' Global 2000 was 80. The company sells Database, database software, particularly Oracle Database, and cloud computing. Oracle's core application software is a suite of enterprise software products, such as enterprise resource planning (ERP) software, human capital management (HCM) software, customer relationship management (CRM) software, enterprise performance management (EPM) software, Customer Experience Commerce (CX Commerce) and supply chain management (SCM) software. History Larry Ellison, Bob Miner, and Ed Oates co-founded Oracle in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unisys OS 2200 Databases
{{Short description, Aspect of Unisys OS 2200 operating system The OS 2200 database managers are all part of the Universal Data System (UDS). UDS provides a common control structure for multiple different data models. Flat files (sequential, multi-keyed indexed sequential, MSAM, and fixed-block), network, and relational data models all share a common locking, recovery, and clustering mechanism. OS 2200 applications can use any mixture of these data models along with the high-volume transaction file system within the same program while retaining a single common recovery mechanism. The database managers are implemented as a protected subsystem and are called procedures in user programs and other subsystems. The database managers support access using many common distributed data access protocols and APIs, including JDBC, OLE DB, and ODBC. The heart of the database and transaction system is Integrated Recovery. "Integrated" implies the integration of all data models, the transa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IDMS
The Integrated Database Management System (IDMS) is a network model (CODASYL) database management system for mainframes. It was first developed at B.F. Goodrich and later marketed by Cullinane Database Systems (renamed Cullinet in 1983). Since 1989 the product has been owned by Computer Associates (now CA Technologies), who renamed it Advantage CA-IDMS and later simply to CA IDMS. In 2018 Broadcom acquired CA Technologies, renaming it back to IDMS. History The roots of IDMS go back to the pioneering database management system called Integrated Data Store (IDS), developed at General Electric by a team led by Charles Bachman and first released in 1964. In the early 1960s IDS was taken from its original form, by the computer group of the B.F. Goodrich Chemical Division, and re-written in a language called Intermediate System Language (ISL). ISL was designed as a portable system programming language able to produce code for a variety of target machines. Since ISL was actually w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Integrated Data Store
Integrated Data Store (IDS) was an early network model , network database, database management system largely used by industry, known for its high performance. IDS became the basis for the CODASYL Data Base Task Group standards. IDS was designed in the 1960s at the computer division of General Electric (which later became Honeywell Information Systems) by Charles Bachman, who received the Turing Award from the Association for Computing Machinery for its creation, in 1973. The software was released in 1964 for the GE-200 series, GE 235 computer. By 1965, a network version for the customer Weyerhaeuser, Weyerhaeuser Lumber was in operation. IDS/II, introduced in 1975, was a . At this time the original version was labeled IDS/I. It was not easy to use or implement applications with IDS, because it was designed to maximize performance using the hardware available at that time. However, that weakness was equally its strength because skilful implementations of IDS-type databases, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HP 3000
The HP 3000 series is a family of 16-bit computing, 16-bit and 32-bit computing, 32-bit minicomputers from Hewlett-Packard. It was designed to be the first minicomputer with full support for time-sharing in the hardware and the operating system, features that had mostly been limited to mainframes, or retrofitted to existing systems like Digital Equipment Corporation, Digital's PDP-11, on which Unix was implemented. First introduced in 1972, the last models reached end-of-life in 2010, making it among the longest-lived machines of its generation. The original HP 3000 hardware was withdrawn from the market in 1973 to address performance problems and OS stability. After reintroduction in 1974, it went on to become a reliable and powerful business system, one that regularly won HP business from companies that had been using IBM's mainframes. Hewlett-Packard's initial naming referred to the computer as the System/3000, and then called it the HP 3000. The HP 3000 originally used a 16-b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IMAGE (database)
IMAGE is a database management system (DBMS) developed by Hewlett-Packard and included with the HP 3000 minicomputer. It was the primary reason for that platform's success in the market. It was also sometimes referred to as IMAGE/3000 in its initial release, and later versions were known as TurboIMAGE, and TurboIMAGE/XL after the PA-RISC migration. IMAGE is based on the network database model, in contrast to most modern systems which are based on the relational database model. A SQL (Structured Query Language) front-end processor was later added, offering users the ability to run SQL queries on existing databases. This produced IMAGE/SQL, the current name. Overview IMAGE consists of several utilities along with an API (referred to as "intrinsics" by the HP documentation): * DBSCHEMA - Compile a source schema layout. The source layout describes the tables (known as SETS) and columns (known as FIELDS). * DBUTIL - Creates and performs maintenance functions on the database. * QUERY - ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
