Joining Strategies: Comprehensive Insight into SQL Join Types

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In SQL, joins are used to combine rows from two or more tables based on a related column between them. There are several types of joins, each serving a different purpose. Here are the main types of SQL joins:

1. INNER JOIN:

• Returns only the rows that have matching values in both tables.
• Syntax:

SELECT * FROM table1
INNER JOIN table2 ON table1.column_name = table2.column_name;

2. LEFT (OUTER) JOIN:

• Returns all rows from the left table and the matched rows from the right table. If there is no match, NULL values are returned for columns from the right table.
• Syntax:

SELECT * FROM table1
LEFT JOIN table2 ON table1.column_name = table2.column_name;

3. RIGHT (OUTER) JOIN:

• Returns all rows from the right table and the matched rows from the left table. If there is no match, NULL values are returned for columns from the left table.
• Syntax:

SELECT * FROM table1
RIGHT JOIN table2 ON table1.column_name = table2.column_name;

4. FULL (OUTER) JOIN:

• Returns all rows when there is a match in either the left or the right table. If there is no match, NULL values are returned for columns from the table without a match.
• Syntax:

SELECT * FROM table1
FULL JOIN table2 ON table1.column_name = table2.column_name;

5. CROSS JOIN:

• Returns the Cartesian product of both tables, i.e., all possible combinations of rows.
• Syntax:

SELECT * FROM table1
CROSS JOIN table2;

6. SELF JOIN:

• Joins a table with itself, treating it as two separate tables.
• Commonly used to find relationships within the same table.
• Syntax:

SELECT * FROM table1 t1
INNER JOIN table1 t2 ON t1.column_name = t2.column_name;

7. NATURAL JOIN: