Differences between INNER JOIN and LEFT JOIN in MySQL

INNER JOIN and LEFT JOIN are two types of join operations in MySQL that are used to combine rows from two or more tables based on a related column between them.

INNER JOIN

INNER JOIN returns only the rows where there is a match between the columns in both tables being joined. If there is no match, the rows are not included in the result set.

LEFT JOIN

LEFT JOIN returns all the rows from the left table (table 1) and the matched rows from the right table (table 2). If there is no match, NULL values are included for the columns from the right table.

When to Use INNER JOIN:

Use INNER JOIN when you only want to retrieve rows that have matching values in both tables.

When to Use LEFT JOIN:

Use LEFT JOIN when you want to retrieve all the rows from the left table, regardless of whether there is a matching row in the right table. This is useful when you want to include rows even if there is no corresponding data in the joined table.

Overall, the choice between INNER JOIN and LEFT JOIN depends on the specific requirements of the query and the desired outcome of the result set.