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COMPUTER SOFTWARE APPLICATION - CITS

Simplicity: The conceptual ER Model construction is straightforward. If we grasp the connections between
attributes and entities, developing the ER Diagram for the model becomes effortless.
Efficient Communication Tool: Database designers extensively rely on this model to effectively convey their
concepts.
Smooth Transition to Various Models: This model harmonizes effectively with the relational model, seamlessly
transforming the ER model into tables. Furthermore, it can be adapted into other models like the network model,
hierarchical model, and more.
Disadvantages of ER Model
Lack of Notation Consistency: An established industry standard for creating an ER model is absent.
Consequently, different developers might employ notations that are unclear to their peers.
Concealed Information: The ER model’s high-level perspective can lead to the omission or concealment of
certain details, potentially resulting in the loss of some information.
Schema

What is Schema?
• The framework of the database takes form through the
attributes, and this framework is identified as the schema.
• A schema outlines the logical limitations, such as tables
and primary keys, that define the structure of a database.

• The schema doesn’t encompass the data attribute types

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CITS : IT&ITES - Computer software application - Lesson 18 - 36