SQL Joins Explained: How to Combine Data Across Multiple Tables

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SQL joins are used to combine rows from two or more tables based on a shared related column. An Inner Join returns only the records that have matching values in both tables, making it the most commonly used join type. A Left Outer Join returns all records from the left table along with any matching records from the right table, filling unmatched columns with NULL. A Right Outer Join works in the opposite direction, returning all records from the right table and matched records from the left. A Full Outer Join returns all records from both tables, with NULL values filling in wherever no match exists on either side.

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