1. Describe the purpose of a conceptual design.
Conceptual design is the first phase or very early phase of the design process. In the
conceptual design phase, designers explore project ideas using a variety of tools, including
drawings, physics models, and 3D rendering of basic preliminary ideas. It usually ignores
technical information such as dimensions so that you can see and change it quickly and easily.
Conceptual design is important for creating a good product. Conceptual design is the stage of
development where engineers and designers work to understand all design problems and find
solutions. This is one of the early stages of development, and you usually need to create a set
of solutions to slowly narrow your design direction.
The result of this step will be reflected later in the details of the design and engineering process,
so concept design should definitely be the first step. The cost of development increases only
with the longer waiting time for a complete and solid concept base. Product success often
depends on how well thought out the initial concept design was.
Conceptual design helps create a clear user interface that is easy to understand and interpret.
It helps to elaborate on the roles and requirements of different users so that they can better
understand the project from the beginning.
Conceptual data model
2. How is a conceptual design different from a logical design?
The main difference between conceptual and logical data model is that conceptual data model
represents entities and their relationships, while logical data model provides more details
including attributes, primary and foreign keys in addition to entities and the relationships.
A conceptual data model is a model that helps to identify the highest-level relationships between
the different entities, while a logical data model is a model that describes the data as much
detail as possible, without regard to how they will be physically implemented in the database.
Logical ERD is a detailed version of a Conceptual ERD. A logical ER model is developed to
enrich a conceptual model by defining explicitly the columns in each entity and introducing
operational and transactional entities. Although a logical data model is still independent of the
actual database system in which the database will be created, you can still consider that if it
affects the design.
Logical data model example
3. What is an external model?
The external model is the display of data by the end user. Databases are typically enterprise
systems that meet the needs of multiple departments. The external model provides the user
with a database endpoint. If you look closely, it can be said that this is similar to the actual
scenario or related if each user observes it. Within the database, there may be restrictions on
certain information contained in the database.
4. What is a conceptual model?
Conceptual data models represent entities and relationships. Entities are real-world objects, and
relationships are associations or dependencies between two entities. The conceptual data
model represents the most important entities and their relationships. No attributes or primary
keys are specified. Overall, the conceptual data model represents important entities and the
relationships between them. That is, no information such as logical or physical data models is
provided. The Conceptual Model Is to Establish the Entities, their Attributes, and their
Relationships.
5. What is an internal model?
The internal model is the process of simulating the response of a system and estimating the
outcome of a system failure. The internal model represents the database in the perspective view
of the database. This model represents the database as a collection of fixed-sized records. That
is, the database contains a fixed size. It can be quite close to the physical layer / file structure.
This is an exact representation of the database.
6. What is a physical model?
Physical ERD represents the actual blueprint of a relational database. The physical data model
details the logical data model by assigning each column a type, length, nullable, and so on.
Because physical ERD represents how to structure and link data in a particular DBMS, it is
important to consider the rules and limitations of the actual database system in which the
database is created. Make sure that the column type is supported by the DBMS and that no
reserved words are used in the names of the entities and columns.
Physical data model example
7. Which model does the database administrator work with?
The Data Administrator is responsible for understanding the business glossary and transforming
it into a logical data model. Data Administrator works with Database Administrator to transform
the model into a real database. System Administrator. They are responsible for installing,
configuring, and setting up your Database Management System.
8. Which model does the end user work with?
The external model is the display of data by the end user. Databases are typically enterprise
systems that meet the needs of multiple departments. The external model requires the designer
to break down a set of requirements and constraints into functional modules that can be
explored within the framework of the external model.
9. What is logical data independence?
Logical data independence is the ability to modify the logical schema without causing
application programs to be rewritten. A logical schema is a conceptual design of a database
created on paper or a whiteboard, like an architectural drawing of a house. The ability to change
the logical schema without changing the external schema or user view is called logical data
independence. For example, you need to be able to add or remove new entities, attributes, or
relationships to this conceptual schema without modifying an existing external schema or
rewriting an existing application program.
10. What is physical data independence?
Physical data independence is the ability to modify the physical schema without causing
application programs to be rewritten. Physical data independence refers to the tolerance of the
internal model to changes in the physical model. Changes to the file organization or storage
structure, storage device, or indexing strategy do not change the logical schema. Physical data
independence is related to hiding storage structure details from user applications. Your
application should not be affected by these issues, as there is no difference in the operations
performed on the data.