Flutter #26 SQL vs NoSQL Databases Explained | How Relations Work + Firebase Overview

Описание: Video Chapters / Headlines
1. Introduction

Quick overview of why we need databases.

Mention SQL (relational) vs NoSQL (non-relational).

Introduce Firebase as a real-world example of NoSQL.

2. What is SQL (Relational Database)?

Data stored in tables (rows + columns).

Each table has a schema (fixed structure).

Uses Primary Keys and Foreign Keys to connect data.

Example:

A Users table with user_id.

An Orders table with order_id and user_id as a foreign key → One-to-Many relation.

SQL ensures data integrity with constraints.

3. What is NoSQL (Non-Relational Database)?

Flexible schema → documents or key-value pairs.

Data often stored as JSON-like objects.

No strict schema, easier to scale horizontally.

Example (using Firebase/Firestore style):

A users collection where each document has user data.

An orders collection where each order has a userId field.

The relation is maintained at the application level, not enforced by the database.

4. SQL vs NoSQL Key Differences

Schema: Fixed in SQL, flexible in NoSQL.

Relations: SQL enforces with foreign keys, NoSQL uses references or embedding.

Scaling: SQL → vertical, NoSQL → horizontal.

Use Cases: SQL for structured data (banking, ERP), NoSQL for flexible and scalable apps (chat apps, social media).

5. Where Firebase Fits

Firebase (Firestore/Realtime DB) is NoSQL.

Stores data in collections & documents.

Developers manage relationships manually:

Embedding (nesting data inside a document).

Referencing (store IDs to connect documents).

6. Practical Example

In SQL: users table & orders table with relations.

In Firebase: users collection & orders collection with userId field.

Show how queries differ (SQL JOIN vs Firestore query).

7. Conclusion

SQL = structured + strong relations.

NoSQL = flexible + scalable.

Firebase is a great NoSQL option for modern apps.

Choose based on project needs.

Description for YouTube

🚀 In this video, we explain the differences between SQL and NoSQL databases and how they handle relationships (one-to-many, many-to-many). You’ll learn:

✅ How SQL databases use tables, primary keys, and foreign keys.
✅ How NoSQL (like Firebase) stores data in collections and documents.
✅ The pros and cons of each database type.
✅ Real-world examples of how relations are represented in SQL vs Firebase.

Perfect for beginners learning databases, Firebase, and MVVM architecture in Flutter apps.