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📚 FULL OUTER JOIN

The FULL OUTER JOIN is used in SQL to return all records when there is a match in either the left or right table.
If there is no match, NULL values are returned for the missing side.

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🛠️ Basic Syntax

SELECT columns
FROM table1
FULL OUTER JOIN table2
ON table1.column_name = table2.column_name;

• FULL OUTER JOIN returns matching records from both tables.
• If there’s no match, it still returns the record with NULL for missing values.

Example

SELECT employees.first_name, departments.department_name
FROM employees
FULL OUTER JOIN departments
ON employees.department_id = departments.department_id;

• This query lists all employees and departments, showing all records even if there is no match.

Key Points

• Combines the results of LEFT JOIN and RIGHT JOIN.
• Rows without a match in one of the tables will have NULL values for that table's columns.
• Not all database systems (like MySQL) support FULL OUTER JOIN natively — workarounds like UNION may be required.

Additional Example

SELECT customers.customer_name, orders.order_id
FROM customers
FULL OUTER JOIN orders
ON customers.customer_id = orders.customer_id;

• This query lists all customers and orders, even if a customer has no orders or an order has no customer.

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🎥 Video Notes

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📝 Problem Description

Describe the problem, challenge, or topic discussed in a video related to SELECT FROM.
What concept was explained or what exercise was solved?

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DataBase Given

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💻 My SQL Code

-- Write your SQL code attempt or solution related to SQL COMMAND
SQL COMMAND

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🧠 Solution Code / Explanation

SQL COMMAND

Explanation - Explain what you learned, any key takeaways, or how you solved the problem related to COMMAND._

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