In the field of business, a model of data is a abstract structure that documents and organizes information for communication between the technical department staff and the rest of the employees. In computing, it differs in terms of its approach, which focuses on the application development planning and the decision of how the data will be stored and how it will be accessed.
Often specified in a language, the data models determine the structure of the information, with the objective of improve communication and accuracy in applications that use and exchange data. These are common areas in which members of a work team with different levels of experience and technical knowledge can interact without problems, given that these models must have a single interpretation.
Data models are essential for the developing of information systems, since through them you can get the necessary compatibility to handle colossal amounts of data. In addition, if the same structures are used for storage and access, then different applications can share information. A clear example is a registration form on a website, where for our name we can only enter letters, and for our date of birth, numbers with a specific order (such as day, month and year). These restrictions respond to the needs of the database and should be the same on two bases as desired. share information.
As a counterpart to the great efficiency they offer, you will find the high cost of development, operation and maintenance of systems and interfaces. Many times, if the quality of the data models implemented is poor, they become obstacles to the growth of a company. Generally, this is obvious when a company that never invested many resources in its digital infrastructure decides that it wants to modernize and discovers that it has a database so inefficient and poorly conceived that it would be easier and less expensive to rebuild everything from the beginning. .
According to the American National Institute of Standards (ANSI) a data model can be interpreted as a scheme:
* conceptual, which specifies the expressions allowed by the model itself, communicates the essential rules and definitions of the data to the users;
* logical, which describes the semantics of tables and columns, object-oriented classes, etc., represented by a particular manipulation technology (such as language SQL);
* physical, which details the means in which the information is stored, such as disk partitions.
Types of database models
Table model: Your definition may not strictly respond to a model; consists of a list of two-dimensional data, in which all the elements of a given column are similar and all the values in a row are related to each other.
Hierarchical model: the information is organized in a tree-like structure, nested so that each element can be branched into many others, which must be sorted in some way.
Network model: structure the information using two fundamental constructions, called records (records) and sets (sets); the former contain fields and the latter define relationships between one to many records (eg, a customer, many products purchased).
Star scheme: usually consists of a table principal, many others are associated with it. A common example is to store the data of a patient in a table, which at the same time will be related to another one where all his consultations are recorded, and with another one in which his claims or his changes of coverage plans are registered, and so on.
