The data model defines how we provide structure for data and how to connect data to other data.
Data modelDefine how we provide structure for data and how to connect data to other data.
We have many different types of data models. They can all be classified into 2 main categories:Conceptual modelwithLogical model.
The most famous conceptual model isEntity relationshipModel, also called ER. This is the best way to organize your data when you are in the design phase, because it is the closest model we believe is the closest and is not linked to any specific implementation.
On the other hand, the logical model isCloser to implementation.
The logical model includes (among others):
- ThisRelationalmodel
- ThisLayeredmodel
- ThisMeshmodel
- Thispurposemodel
You can see that the name has provided us with hints on how to implement these models: the table of the relational model, the tree of the hierarchical model, the graph of the mesh model, the object of the object model.
ThisRelational modelWe will introduce this logical model in detail soon because it is the basis of popular relational databases (including PostgreSQL, MySQL, SQLite, and SQL Server).
Conceptual model and logical model are two different tools. Using one does not exclude the other. We can start with the conceptual model, and then use the logical model to implement it.
More database tutorials:
- MongoDB basic tutorial
- How is MongoDB different from SQL database
- Information system, data and information
- Data model
- Introduction to ER data model
- Relational model
- Relational algebra
- relational database
- What is a database? There is also a DBMS?
- Introduction to SQL
- How to install PostgreSQL on macOS
- Do you always need to provide a database for the application?
- How to install SQLite on macOS
- Introduction to PostgreSQL
- PostgreSQL user permissions
- How to list all users in PostgreSQL
- How to switch database using PostgreSQL
- How to list all databases using PostgreSQL
- How to use PostgreSQL to list the tables in the current database
- How to install MySQL on macOS
- Create user on MySQL
- PostgreSQL vs MySQL, comparison
- SQLite user permissions
- MySQL user permissions
- SQL, create table
- SQL, add data to the table
- SQL, how to use SELECT
- SQL, handle empty cells
- SQL, unique key and primary key
- SQL, how to update data
- SQL, how to update the table structure
- SQL, how to delete data and tables
- SQL connection
- SQL view
- How to insert multiple items in a MongoDB collection at once
- How to delete all items from MongoDB collection