Difference between inner join and outer join in MySQL

Joins are used to get the records from two OR more tables. Following are different type of joins  used in mysql.

• Left Join
• Right Join
• Inner Join
• Self Join
• Outer Join

Following are difference between Inner Join & Outer Join.

Inner Join: It is used to get the common records from two table or more tables.

MySQL Inner Join Example:

SELECT * FROM `geo_cities` as gc INNER JOIN meta_data AS md on md.city_id=gc.id;

Outer Join: It is used to get the all records from two tables or more tables.

MySQL Outer Join Example:
MySQL does not provide the FULL JOIN.
You need to UNION the result of Right Join and Left Join from both tables.

SELECT * FROM `geo_cities` as gc LEFT JOIN meta_data AS md on md.city_id=gc.id
UNION
SELECT * FROM `geo_cities` as gc RIGHT JOIN meta_data AS md on md.city_id=gc.id

Best Related Posts are Following:

1. Difference between MVC and MVP design pattern.
2. Difference between theme and template in website.
3. Difference between in_array and array_key_exists in php with Example.
4. Difference between SSL and HTTPS.
5. Difference between overloading and overriding in php with Example.
6. What is difference between natcasesort and sort?.
7. Difference Between Hadoop and Big-Data.
8. Difference Between Primary Key And Unique Key And Foreign Key And Composite Key.
9. PHP Sessions and Cookie and Security.
10. Difference between WebService and API.
11. Difference Between MyISAM and innoDB - MySQL.