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.
Generally, data modelling is the process of creating a data model of the available data. A data model represents data objects and associations between data objects. Overall, this process helps to visually represent data and to take business insights. There are various types of data models, and two of them are conceptual and logical data model.
Key Areas Covered
1. What is Conceptual Data Model
–Definition, Functionality
2. What is Logical Data Model
-Definition, Functionality
3. Difference Between Conceptual and Logical Data Model
-Comparison of key differences
Key Terms
Conceptual Data Model, Data Modelling, Logical Data Model
What is Conceptual Data Model
A conceptual data model represents the entities and relationships. An entity is a real-world object, while a relationship is an association or a dependency between two entities. The conceptual data model represents the most important entities and their relationships. It does not specify the attributes or primary key. In overall, the conceptual data model represents the essential entities and the relationships among the entities. In other words, it does not provide information like logical or physical data models.
What is Logical Data Model
A logical data model describes the data to a greater extent than the conceptual model. However, it is not used to build a real database. It includes all the entities, relationships and attributes. These attributes denote the characteristics or properties of an entity. Additionally, a logical data model also consists of a primary key and a foreign key. Furthermore, it is possible to apply normalization. Generally, the normalization level is the third normal form (3NF).
In addition to the conceptual and logical model, there is another data model called the physical data model. It helps to implement the actual database. It is more complex than the logical data model contains details on table names, column names and column data types.
Difference Between Conceptual and Logical Data Model
Definition
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. Thus, this explains the main difference between conceptual and logical data model.
Consist of
Moreover, the conceptual data model consists of entities and the relationships between the entities, while logical data model consists of entities, attributes, relationships, primary keys and foreign keys.
Attributes
Besides, another difference between conceptual and logical data model is that while a conceptual data model does not represent attributes, a logical data model represents attributes.
Primary key / foreign key
Furthermore, the conceptual data models do not specify primary keys and foreign keys, while the logical models specify primary keys and foreign keys.
Usage
Additionally, the conceptual data model is the basis for developing the logical data model, while the logical data model is the basis for developing the physical data model.
Complexity
Also, the conceptual data models are simpler than the logical data models.
Conclusion
In brief, data modelling is the process of recognizing the data that has to be stored in a database. Furthermore, there are three main models involved in data modelling. Two of them are conceptual and logical data modelling. 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 than the conceptual data model including attributes, primary and foreign keys other than the entities and the relationships.
References:
1.“Data Modeling.” Data Modeling – Conceptual, Logical, and Physical Data Models, Available here.
2. “Conceptual Data Model.” 1KeyData, Available here.
3. “Logical Data Model.” 1KeyData, Available here.
Image Courtesy:
1.”1895779″ via Pixabay
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