Creating multiple-to-multiple relationships in Express: A beginner's guide

In developing a small API with Express and TypeScript, I am faced with handling both POST and GET requests. The POST request involves receiving a list of organizations, which may have daughter organizations that can also have their own daughters, creating a complex hierarchical structure.

One approach I am considering is setting up two database tables in postgreSQL: Organization and Parent_child.

Organization{
   id: number,
   name: string
}

Parent_child{
    parent_id: number,
    child_id: number
}

My goal is to establish a many-to-many relationship between Organization entities through the Parent_child table. Although I have tried exploring various resources on how to manipulate databases, most tutorials lack clarity.

Do you have any recommendations or suggestions on how to achieve this kind of relationship? I have come across sequelize and typeORM as potential solutions, but their documentation has been confusing for me so far.

Answer №1

Follow the comprehensive instructions to establish a connection between sequelize and your Postgres database, then create your models following the documentation example... be meticulous when defining associations in your models.. I found belongsToMany a bit challenging initially, but if you encounter any difficulties, feel free to reach out here and I'll help pinpoint where you might have made a mistake

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