Moving from Single Tables to Real-World Database Design

Up until now, we’ve spent a good amount of time writing basic SQL.

But if we’re being honest, the SQL we’ve written so far doesn’t really reflect how things work in the real world.

So far:

• We worked with a cities table in one database
• We worked with a phones table in another database
• Each database had only one table

This is great for learning SQL basics, but it’s not how real applications work.

Reality Check: Real Apps Don’t Use One Table

In real-world applications:

• Databases almost never have just one table
• Data is spread across multiple tables
• Tables are connected to each other through relationships

Yes, it’s possible to have a single-table database, but you’ll almost never see that in professional systems.

So if we want to learn SQL properly, we need to move closer to reality.

What’s Next?

From this point onward, we’re going to work with:

• multiple tables
• relationships between tables
• more realistic database designs

To do this, we’ll design a database for a photo-sharing application.

This will be a bit more challenging — but that’s a good thing.

Because this is the kind of work you’ll actually do when working with PostgreSQL in real projects.

Example: A Photo Sharing Application