SQLite Inner Join

Introduction

SQLite is a widely used relational database management system. One of the essential features of SQLite is that it supports various types of joins, such as inner join, left join, right join and outer join. In this article, we will dive deep into SQLite inner join, which is one of the fundamental types of join.

What is Inner Join?

Inner join is a type of join that returns only the rows from both tables that have matching values. In other words, inner join combines the content of two tables based on a common column, disregarding any unmatched rows. Inner join can be used to extract data that fits specific criteria from two different tables.

Syntax

The syntax for inner join in SQLite is as follows:

SELECT column1, column2…
FROM table1
JOIN table2
ON table1.common_column=table2.common_column;

• column1, column2, etc. are the columns we want to retrieve in the output.
• table1, table2 are the tables we want to join.
• common_column is the column on which we want to join the two tables.

Example

Let's consider an example where we want to join two tables, customers and orders, based on the common column customer_id. The following SQL query will retrieve all the customer names along with the order number and date:

SELECT customers.customer_name, orders.order_number, orders.order_date
FROM customers
JOIN orders
ON customers.customer_id=orders.customer_id;

Here, we select the columns we want to retrieve in the output, customer_name, order_number, and order_date, from the two tables customers and orders. We use the JOIN keyword to join the two tables on the common column customer_id, which ensures that we only retrieve the matching rows from both tables.

Conclusion

In this article, we have explored the inner join in SQLite. Inner join is a powerful tool that helps programmers retrieve data from two tables based on a common column. We have discussed the syntax and provided an example of how to use inner join to combine data from two different tables. By understanding inner join, programmers can write more efficient SQL queries and retrieve the desired data more effectively.