Search results
Results From The WOW.Com Content Network
Consequently, the ER model becomes an abstract data model, [1] that defines a data or information structure that can be implemented in a database, typically a relational database. Entity–relationship modeling was developed for database and design by Peter Chen and published in a 1976 paper, [ 2 ] with variants of the idea existing previously ...
The logical data structure of a DBMS, whether hierarchical, network, or relational, cannot totally satisfy the requirements for a conceptual definition of data because it is limited in scope and biased toward the implementation strategy employed by the DBMS. That is unless the semantic data model is implemented in the database on purpose, a ...
The enhanced entity–relationship (EER) model (or extended entity–relationship model) in computer science is a high-level or conceptual data model incorporating extensions to the original entity–relationship (ER) model, used in the design of databases.
Enterprise data modelling or enterprise data modeling (EDM) is the practice of creating a graphical model of the data used by an enterprise or company. Typical outputs of this activity include an enterprise data model consisting of entity–relationship diagrams (ERDs), XML schemas (XSD), and an enterprise wide data dictionary.
ERD—Entity–Relationship Diagram; ERM—Entity–Relationship Model; ERP—Enterprise Resource Planning; eSATA—external SATA; ESB—Enterprise service bus; ESCON—Enterprise Systems Connection; ESD—Electrostatic Discharge; ESI—Electronically Stored Information; ESR—Eric Steven Raymond; ETL—Extract, Transform, Load; ETW—Event ...
Attributes and ties can be historized when changes in the information they model need to be kept. An example model showing the different graphical symbols for all the concepts can be seen below. The symbols resemble those used in entity–relationship modeling, with a couple of extensions. A double outline on an attribute or tie indicates that ...
The dimensional model is a specialized adaptation of the relational model used to represent data in data warehouses in a way that data can be easily summarized using online analytical processing, or OLAP queries. In the dimensional model, a database schema consists of a single large table of facts that are described using dimensions and measures.
The following is provided as an overview of and topical guide to databases: Database – organized collection of data, today typically in digital form. The data are typically organized to model relevant aspects of reality (for example, the availability of rooms in hotels), in a way that supports processes requiring this information (for example, finding a hotel with vacancies).