What are the different types of Join used in SQL?

Question

Accepted Answer

Different types of joins in SQL include inner join, left join, right join, and full outer join.

Inner join returns only the matching rows from both tables
Left join returns all rows from the left table and the matching rows from the right table
Right join returns all rows from the right table and the matching rows from the left table
Full outer join returns all rows from both tables, including unmatched rows

Accepted Answer

In SQL, there are several types of joins that can be used to combine data from multiple tables based on a common field. The most common types of joins are:

Inner Join: Returns only the matching rows from both tables based on a specified join condition.
Syntax: SELECT columns FROM table1 INNER JOIN table2 ON table1.column = table2.column;
Left Join (or Left Outer Join): Returns all rows from the left table and matching rows from the right table based on a specified join condition. If there are no matching rows in the right table, the result will contain NULL values for the right table columns.
Syntax: SELECT columns FROM table1 LEFT JOIN table2 ON table1.column = table2.column;
Right Join (or Right Outer Join): Returns all rows from the right table and matching rows from the left table based on a specified join condition. If there are no matching rows in the left table, the result will contain NULL values for the left table columns.
Syntax: SELECT columns FROM table1 RIGHT JOIN table2 ON table1.column = table2.column;
Full Outer Join (or Full Join or Cross Join): Returns all rows from both tables, matching rows from both tables, and NULL values for non-matching rows.
Syntax: SELECT columns FROM table1 FULL JOIN table2 ON table1.column = table2.column;
Self Join: Joins a table to itself, typically used to compare rows within the same table based on a common field.
Syntax: SELECT columns FROM table1 t1 INNER JOIN table1 t2 ON t1.column = t2.column;

Each type of join serves a specific purpose and can be used to combine data from multiple tables in different ways.

Accepted Answer

There are 4 types of joins in SQL ,inner,outer,left join,right join

What are the different types of Join used in SQL?

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