An INNER JOIN in SQL is a method for combining rows from two or more tables based on a related column between them. The join condition is specified using the ON keyword, indicating which columns in each table should have matching values for the rows to be included in the result set.

Syntax

SELECT * 
FROM table1
INNER JOIN table2 
ON table1.column_name = table2.column_name;

Example

Let’s consider two tables, employees and departments

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Now, let’s perform an INNER JOIN to retrieve information about employees and their corresponding departments:

Database Exercise

Database Schema:

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Exercise Script:

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Available actions: Execute

Result

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In this example, the INNER JOIN is based on the equality of the department_id columns in both tables. The result set includes only the rows where there is a match between the department_id values in the employees and departments tables. As a result, we get a cohesive view of employees and their respective departments.