How do SQL JOINs work?

Computer Science

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orders.useridreturnsonlyuserswhohaveorders.orders.user_id — returns only users who have orders.

SQL JOINs combine rows from multiple tables based on related columns. Types: INNER JOIN: only matching rows from both tables. LEFT JOIN: all rows from left table + matching from right (NULL if no match). RIGHT JOIN: opposite of LEFT. FULL OUTER JOIN: all rows from both, NULLs where no match. CROSS JOIN: every combination (cartesian product). Example: SELECT users.name, orders.total FROM users INNER JOIN orders ON users.id = orders.user_id — returns only users who have orders.

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SQL JOINs combine rows from multiple tables based on related columns. Types: INNER JOIN: only matching rows from both tables.

How do SQL JOINs work?
Computer Science

This computer science problem involves algorithmic thinking and programming concepts. The solution below explains the approach, logic, and implementation step by step.

ScanSolve AI Answer
SQL JOINs combine rows from multiple tables based on related columns. Types: INNER JOIN: only matching rows from both tables. LEFT JOIN: all rows from left table + matching from right (NULL if no match). RIGHT JOIN: opposite of LEFT. FULL OUTER JOIN: all rows from both, NULLs where no match. CROSS JOIN: every combination (cartesian product). Example: SELECT users.name, orders.total FROM users INNER JOIN orders ON users.id = orders.user_id — returns only users who have orders.