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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