What is the difference between schema, model and entity?

Question

Design patterns

What is the difference between schema, model and entity?
MVC

Answer 1

If I understand correctly what you want to know, then this is the story.
A model is an object described in the code, a class that is needed for manipulation at the abstraction level. The model serves as a wrapper over the entity. You simply describe in it all the properties and methods inherent in it (if they are needed). For example, you can create a database table model (inheriting from some base model), in which you describe all properties (columns), specify their (column) parameters, etc.
An entity is what the model stores, a unique instance , obtained from the model. That is, if it was a database table model, then the entity will be a specific record with a primary key.
Schemeis the connection of the models. That is the scheme of their interaction. If we take the same database table model, then if it has a foreign key to another table, then they will have a connection and a scheme of interaction between themselves through their models.

Answer 2

Model - some abstraction of what we design (model):
- or a business abstraction model, whether it be entities (payment, goods, order) with a state or whether it is business processes (ordering goods, writing off balance for purchase, dismissal) without state or collection
- or a data/storage model (e.g. images)
- or a model of anything that we have designed, except for infrastructure details and related details (controllers for example), if this is not the basic essence of our code
Entity - a business model , which has an explicit identifier and its own state (a specific document, a specific user, a specific payment, where the specificity is due to some unique identifier
)- an abstract plan of something (connections or processes for example)