[RAILS] Relationship between database and model (basic)

About files related to the database

Purpose: I wrote this article because I thought that I had to understand the difference between the roles of model files and migration files in order to resolve errors.

Currently: We are in the final stage of portfolio creation, but there are still many things we do not understand, and we realize that we do not have enough basic understanding, and we are understanding from the mechanism while solidifying the basics.

Role of model file

This file shows the access authority to the database.
The model and association described indicate the access authority to the database through the model.

Why can't I retrieve this data? To understand, look at the model file that describes the access rights to the database. And it is the first step towards understanding.

Role of migration file

A file that describes the information required to store the contents of the data.
When passing data, specify the table name (class) and column name described in the file.

Why specify the table name (class)?


Understand both together

You will be able to understand the basics of how data is received from the database.

Unrelated models and models


Understanding the MVC phase

Advantages (impressions) of publishing the output

Do you really understand yourself? By writing while thinking many times, I was able to establish my knowledge.
Also, I don't know if it was a useful article for someone, but by publishing it on my blog, I was able to deeply understand and train my ability to communicate.
Thank you to everyone who read it.
If you have any mistakes, please do not hesitate to comment.

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