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A hierarchical database model is a data model in which the data is organized into a tree-like structure. The data are stored as records which is a collection of one or more fields . Each field contains a single value, and the collection of fields in a record defines its type .
A Warnier/Orr diagram (also known as a logical construction of a program/system) is a kind of hierarchical flowchart that allows the description of the organization of data and procedures. They were initially developed 1976, [ 1 ] in France by Jean-Dominique Warnier [ 2 ] and in the United States by Kenneth Orr [ 3 ] on the foundation of ...
In the object-oriented application programming paradigm, which is related to database structure design, UML class diagrams may be used for object modeling. In that case, object relationships are modeled using UML associations, and multiplicity is used on those associations to denote cardinality .
The nested set model is a technique for representing nested set collections (also known as trees or hierarchies) in relational databases. It is based on Nested Intervals, that "are immune to hierarchy reorganization problem, and allow answering ancestor path hierarchical queries algorithmically — without accessing the stored hierarchy relation".
Data hierarchy refers to the systematic organization of data, often in a hierarchical form. Data organization involves characters, fields, records, files and so on. [1] [2] This concept is a starting point when trying to see what makes up data and whether data has a structure. For example, how does a person make sense of data such as 'employee ...
A process flow diagram describing the construction of a structure chart by a so-called Subject Matter Experts (SME). [2]According to Wolber (2009), "a structure chart can be developed starting with the creating of a structure, which places the root of an upside-down tree which forms the structure chart.
SADT uses two types of diagrams: activity models and data models. It uses arrows to build these diagrams. The SADT's representation is the following: A main box where the name of the process or the action is specified; On the left-hand side of this box, incoming arrows: inputs of the action.
The basic data structure of the relational model is the table, where information about a particular entity (say, an employee) is represented in rows (also called tuples) and columns. Thus, the " relation " in "relational database" refers to the various tables in the database; a relation is a set of tuples.