MySQL Joins tutorial; Through this tutorial, we would love to share with you how to use MySQL JOINS with the help of examples.
JOINS can be used in MySQL with the Select Statement. It is used to get data from many database tables. When we want to get the records from two or more database tables, then we need to use MySQL JOINS at that time.
MySQL JOINS Tutorial: INNER, OUTER, LEFT, RIGHT, CROSS
Basically MySQL Provide three types of Join INNER JOIN, LEFT JOIN, RIGHT JOIN & SELF JOIN.
- INNER JOIN MySQL
- LEFT JOIN MySQL
- RIGHT JOIN MySQL
- SELF JOIN MySQL
INNER JOIN MySQL
In MySQL INNER JOIN clause selects records if the given column values matching in both tables. MySQL INNER JOIN is used to fetch data from multiple tables.
Syntax
SELECT table1.column, table2.column
FROM table1
INNER JOIN table2
ON table1.column = table2.column;
INNER JOIN MySQL Example
If we want to select data from two country and city, then we can run the following query (Inner Join) :-
SELECT city, country FROM city INNER JOIN country ON city.country_id = country.country_id;
LEFT JOIN MySQL
The MySQL LEFT JOIN clause returns all rows from the left table, even if there are no matches in the right table, The result is NULL from the right side.
Syntax
SELECT column_name(s)
FROM table1
LEFT JOIN table2
ON table1.column_name = table2.column_name;
LEFT JOIN MySQL Example
Let’s return a list of all users table. And if the users shares the same last name with an actor table :-
SELECT u.user_id, u.first_name, u.last_name, a.autor_id, a.first_name, a.last_name FROM users u LEFT JOIN actor a ON u.last_name = a.last_name ORDER BY u.last_name;
Right JOIN MySQL
The MySQL Right JOIN clause returns all rows from the right table, even if there are no matches in the right table, The result is NULL from the right side.
Syntax
SELECT column_name(s)
FROM table1
Right JOIN table2
ON table1.column_name = table2.column_name;
Right JOIN MySQL Example
Let’s return a list of all users table. And if the users shares the same last name with an actor table :-
SELECT u.user_id, u.first_name, u.last_name, a.autor_id, a.first_name, a.last_name FROM users u RIGHT JOIN actor a ON u.last_name = a.last_name ORDER BY a.last_name;
Self Join MySQL
The MySQL self join is used to join a table to itself when using a join clause.
MySQL self join is useful when you want to combine the records in a table with other records in the same table.
Self Join MySQL Example
SELECT a.customer_id, a.first_name, a.last_name, b.customer_id, b.first_name, b.last_name FROM customer a INNER JOIN customer b ON a.last_name = b.first_name;
Note
MySQL Self join can also use with left join and right join
Conclusion
In this MySQL joins tutorial- we have learned how to many types of joins in mysql and how to use mysql joins with the help of examples.
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