Gain insights into fundamental database concepts, relational databases, and entity-relationship diagrams. Learn about normalization techniques and basics of SQL to enhance database efficiency.

Databases are universal - they underlie the technology you use every day. They're a crucial component of everything from telecommunications systems, banking systems, and video games to just about any other software system that maintains some amount of persistent data.

In this course, you'll learn about the fundamental concepts of databases, why and when they're used, what relational databases are, and entity-relationship diagrams. You will also be exposed to techniques like normalization that help to increase the efficiency of databases. You'll wrap up with a look at the basics of Structured Query Language (SQL). 

After completing this course, you will be able to move onto more advanced courses involving database systems and SQL.

Database Design Fundamentals for Software Engineers

# INNER JOIN

The **INNER JOIN** keyword selects records that have matching values in both tables.

## Syntax

The basic syntax of the `INNER JOIN` is as follows:

```sql
SELECT table1.column1, table2.column2 ... 

FROM table1

INNER JOIN table2

ON table1.common_field = table2.common_field;
```

## Example

We will be using the CUSTOMERS and ORDERS tables as defined in the previous lesson.

Let's say we want to retrieve the information of only those customers that have placed an order. This can be done by joining the two tables:




In this lesson, we will study the INNER JOIN in SQL.

Introduction

Fundamental Concepts

Data Modeling

Entity-Relationship Data Model

The Relational Data Model

Functional Dependencies

Normalization

Structured Query Language

Conclusion

INNER JOIN

INNER JOIN

Syntax