Friday, February 22, 2019

Data Model

Data Model:
Data models define how the logical structure of a database is modeled. Data Models are fundamental entities to introduce abstraction in a DBMS. Data models define how data is connected to each other and how they are processed and stored inside the system. A database model is a type of data model that determines the logical structure of a database and fundamentally determines in which manner data can be stored, organized and manipulated. It describes the design of database to reflect entities, attributes, relationship among data, constrains etc.
It involves planning about tables, their columns, mapping between the tables, how they are structured in the physical memory etc. A data model helps to put the real world requirement into a design. This makes the developer to understand the relationship between various objects in the database. It helps to highlight any drawbacks of the plan and correct it at the design stage itself.
The very first data model could be flat data-models, where all the data used are to be kept in the same plane. Earlier data models were not so scientific, hence they were prone to introduce lots of duplication and update anomalies.
Features / Benefits of Data Model:
1.      It provides a means to represent a real world object in to computer – usable form.
2.      It captures and represents associations and relationships among the real world objects.
3.      It defines how the objects in the application interact in logical terms.
4.      It allows the database designer to capture static and dynamic organization and flow of information within a modeled enterprise. 
Depending on the levels of data, data models are divided into 3 categories:
·        Object Based Data Models:
o   Object Oriented Model
o   Entity Relational Model
·        Record based Data models:
o   Relational Data Model
o   Network Data Model
o   Hierarchical Model
       ·        Physical Data Model

-profshardulp.patil@gmail.com

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