Should I Deal with IDs or with Models in Sequelize?

Описание: Exploring the best approach for handling products in orders using Sequelize ORM: Should you work with full model objects or just IDs?
---
This video is based on the question https://stackoverflow.com/q/74908541/ asked by the user 'Mohammad ARZ' ( https://stackoverflow.com/u/18762375/ ) and on the answer https://stackoverflow.com/a/74921555/ provided by the user 'Ralle Mc Black' ( https://stackoverflow.com/u/10692906/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: should i deal with ID's or with models

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Should I Deal with IDs or with Models in Sequelize?

When working with a database, particularly through an Object-Relational Mapping (ORM) tool like Sequelize, a common question arises: should you manage database records using complete model objects or just their IDs? This question is especially pertinent when dealing with many-to-many (M2M) relationships, such as assigning products to orders.

In this guide, we will examine the implications of each approach, especially in the context of using Sequelize for a product order system, and determine which method may enhance performance and maintain structure in your application.

The Problem: Working with Products in Orders

In your scenario, you are trying to set products for an order using the M2M relationship provided by Sequelize. You might attempt to simply pass an array of IDs like this:

[[See Video to Reveal this Text or Code Snippet]]

Conversely, when you provide full product objects, as shown below, it works:

[[See Video to Reveal this Text or Code Snippet]]

This raises a couple of questions. Is working with full object representations beneficial for performance, or should you lean towards using only IDs, retrieving full models as needed?

Understanding setProducts in Sequelize

The setProducts function is tied to your Sequelize model's associations. It is designed to establish relationships between your models—in this case, between Orders and Products.

Why IDs Alone Don’t Work

When you try to set products using just their IDs, you encounter an issue because Sequelize expects complete object definitions based on the association rules defined in your models.

Complete objects provide Sequelize with enough data to establish the relationships correctly, which cannot be achieved with IDs alone unless they are handled via an intermediary table.

Solution: Use an Additional Table

To address the original question, you can indeed work with just ID values if you establish a specific structure in your database. Here’s how you can handle it efficiently:

1. Create a Join Table

Utilize a join table where you can store both the order ID and product IDs in one place. This approach forms a normalized data structure, where direct relationships between orders and products are maintained without redundancy.

2. Use Sequelize Methods

Instead of always passing complete product objects, consider using Sequelize methods to retrieve product details only when necessary. For instance:

[[See Video to Reveal this Text or Code Snippet]]

Benefits of This Approach

Performance: Working primarily with IDs can improve performance, especially in cases where you may not need all product details immediately.

Clean Data Structure: A join table keeps your database schema well-structured and normalized, making it easier to manage relationships without repeating data unnecessarily.

3. Carving Out an Efficient Workflow

To integrate this strategy seamlessly into your application:

Create/Update: Use full product objects when creating new orders but transition to a more ID-focused workflow for existing records and updates.

Fetching Data: Only load product data when required, keeping your application lightweight and responsive.

Conclusion: Choosing Between IDs and Objects

While Sequelize offers the flexibility to work with both methods, a structured approach using an intermediary join table can lead to a more optimized and maintainable system. It allows you to work with IDs to improve performance while still having the ability to retrieve complete model information when necessary. So, as a best practice, consider establishing that additional structuring in your database and switching to an ID-focused approach wherever applicable.

By following these guidelines, you’l