Describe your experience writing queries using joins.

Question

Accepted Answer

Joins in SQL combine rows from two or more tables based on related columns.

INNER JOIN: Returns records with matching values in both tables. Example: SELECT * FROM Orders INNER JOIN Customers ON Orders.CustomerID = Customers.CustomerID;
LEFT JOIN: Returns all records from the left table and matched records from the right table. Example: SELECT * FROM Customers LEFT JOIN Orders ON Customers.CustomerID = Orders.CustomerID;
RIGHT JOIN: Returns all records from the right table and matched records from the left table. Example: SELECT * FROM Orders RIGHT JOIN Customers ON Orders.CustomerID = Customers.CustomerID;
FULL OUTER JOIN: Returns all records when there is a match in either left or right table records. Example: SELECT * FROM Customers FULL OUTER JOIN Orders ON Customers.CustomerID = Orders.CustomerID;
CROSS JOIN: Returns the Cartesian product of two tables. Example: SELECT * FROM Products CROSS JOIN Categories;

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