How many types of Join do you know?

Types of join: -   
1)    Inner Join
2)    Outer Join
Left Outer Join
Right Outer Join
Full Outer Join
3)    Cross Join

1)    Inner Join- It return rows when there is at least one match in both tables.
SELECT column_name(s) FROM table_name1 INNER JOIN table_name2 ON table_name1.column_name = table_name2.column_name.
2)    Left Outer Join – It returns all rows from the left table (table_name1), even if there are no matches in the right table (table_name2).
SELECT column_name(s) FROM table_name1 LEFT JOIN table_ name2 ON table_name1.column_name = table_name2.column_name.
3)    Right Outer Join – It returns all rows from the right table (table_name2), even if there are no matches in the left table (table_name1).
SELECT column_name(s)  FROM table_name1 RIGHT JOIN table_name2 ON table_name1.column_name = table_name2.column_name
4)    Full Outer Join – It returns rows when there is a match in one of the tables.
SELECT column_name(s) FROM table_name1 FULL JOIN table_name2 ON table_name1.column_name = table_name2.column_name
5)    Cross Join – A cross join will return a result table where each row from the first table is combined with each row from the second table. The number of rows in the result table is the product of the number of rows in each table. If the tables involved are large, this join can take a very long time.

A cross join cam be specified in two ways: using the JOIN syntax or by listing the tables in the FROM clause separated by commas without using a WHERE clause to supply join criteria.

SELECT * FROM A CROSS JOIN B

SELECT * FROM A, B