Define Join and explain different type of joins?

Answer

Another frequently asked SQL Interview Questions on Joins. In order to avoid data duplication, data is stored in related tables. Join keyword is used to fetch data from related tables. "Join" return rows when there is at least one match in both table. Type of joins are

Right Join 
Return all rows from the right table, even if there are no matches in the left table.

Outer Join

Left Join
Return all rows from the left table, even if there are no matches in the right table.

Full Join
Return rows when there is a match in one of the tables.