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  2. Database schema - Wikipedia

    en.wikipedia.org/wiki/Database_schema

    The database schema is the structure of a database described in a formal language supported typically by a relational database management system (RDBMS). The term " schema " refers to the organization of data as a blueprint of how the database is constructed (divided into database tables in the case of relational databases ).

  3. Data modeling - Wikipedia

    en.wikipedia.org/wiki/Data_modeling

    The database design documented in these schemas is converted through a Data Definition Language, which can then be used to generate a database. A fully attributed data model contains detailed attributes (descriptions) for every entity within it. The term "database design" can describe many different parts of the design of an overall database ...

  4. Data-flow diagram - Wikipedia

    en.wikipedia.org/wiki/Data-flow_diagram

    The warehouse (datastore, data store, file, database) is used to store data for later use. The symbol of the store is two horizontal lines, the other way of view is shown in the DFD Notation. The name of the warehouse is a plural noun (e.g. orders)—it derives from the input and output streams of the warehouse.

  5. Tuple relational calculus - Wikipedia

    en.wikipedia.org/wiki/Tuple_relational_calculus

    A relational database schema is defined as a tuple S = (D, R, h) where D is the domain of atomic values (see relational model for more on the notions of domain and atomic value), R is a finite set of relation names, and h : R → 2 C. a function that associates a header with each relation name in R. (Note that this is a simplification from the ...

  6. Conceptual schema - Wikipedia

    en.wikipedia.org/wiki/Conceptual_schema

    A conceptual schema or conceptual data model is a high-level description of informational needs underlying the design of a database. [1] [2] It typically includes only the core concepts and the main relationships among them. This is a high-level model with insufficient detail to build a complete, functional database. [3]

  7. Logical schema - Wikipedia

    en.wikipedia.org/wiki/Logical_schema

    A logical data model or logical schema is a data model of a specific problem domain expressed independently of a particular database management product or storage technology (physical data model) but in terms of data structures such as relational tables and columns, object-oriented classes, or XML tags.

  8. Database model - Wikipedia

    en.wikipedia.org/wiki/Database_model

    Database model for MediaWiki 1.28.0 (2017) Different types of database models A database model is a type of data model that determines the logical structure of a database.It fundamentally determines in which manner data can be stored, organized and manipulated.

  9. Network model - Wikipedia

    en.wikipedia.org/wiki/Network_model

    Bachman diagram of a simple network database. 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 ...