Welcome to findnerd, today we are going to discuss to join in MySQL.

Firstly let know what is join ?

An SQL JOIN clause is used to combining two or more tables and return output in single table.
So in simple word we can say that MySQL joins basically merge two or more than two tables together to form a single table.

There are mainly four types of join in MySQL,these are given bellow.

 1-Inner join 
 2-Outer join
 3-Left join 
 4-Right join 

Now let explain one by one

1-Inner join:- Inner join returns all rows when there is at least one match in BOTH tables,
means if there is any common key(primary and foreign key) in both tables.

syntax of inner join

 SELECT column_name(s)
  FROM table1
  JOIN table2
  ON table1.column_name=table2.column_name;

2-Outer join:-Outer join displays all rows from left table and right table. if there are rows in left table which does not matches with the rows in right table , those rows will also be displayed and viceversa.

syntax of FULL outer join

SELECT column_name(s)
    FROM table1
    FULL OUTER JOIN table2
    ON table1.column_name=table2.column_name;

3-Left join:-Left join return all rows from the left table, if there is no match in the right table.

syntax of left join

SELECT column_name(s)
  FROM table1
  LEFT JOIN table2
  ON table1.column_name=table2.column_name;

4-Right join:-Right join return all rows from the right table, af there is no match in the left table.

syntax of right join

 SELECT column_name(s)
    FROM table1
    RIGHT JOIN table2
    ON table1.column_name=table2.column_name;