How do SQL joins handle null values?

How do SQL joins handle null values?

SQL joins can handle null values in different ways depending on the type of join used. For example, in a LEFT JOIN, if there are no matching records in the right table, the result will include nulls for those columns.

What happens in an INNER JOIN when there are nulls?

In an INNER JOIN, rows with null values in the join condition will be excluded from the result set. Only rows with matching values in both tables will be returned.

Can you give an example of a LEFT JOIN with null values?

Sure! If you have a table of customers and a table of orders, a LEFT JOIN will return all customers, including those who haven't placed any orders, showing nulls for order details.

How can I filter out nulls after a join?

You can use the WHERE clause to filter out nulls. For example, you can add WHERE orders.id IS NOT NULL to exclude rows where the order ID is null.