# INNER JOIN

A join returning only row combinations that satisfy its join condition.

## What is **INNER JOIN** in a relational database?

**INNER JOIN** — A join returning only row combinations that satisfy its join condition.

```sql
SELECT customer.email, purchase_order.order_id
FROM customer
INNER JOIN purchase_order
    ON purchase_order.customer_id = customer.customer_id;
```

Level: Apprentice · [More Database terms at this level](https://www.ask-codey.com/glossary/subjects/database/apprentice)

Updated: September 27, 2026

Source: https://www.ask-codey.com/glossary/inner-join