What is the difference between inner and outer join? Explain with example.

This is one of the common questions I see in any Interview :)

https://www.w3schools.com/sql/sql_join.asp

Inner join get data of matching records from tables only. Outer join get data even there is no match found in another table

Inner join is join where all matched rows returned.there are no single outer join,there are left outer join and right outer join.if you use left outer join it will return results of matched rows and also return rows Left table.if you use left outer join it will return results of matched rows and also return rows right table. Example of inner join: select * from emp e inner join dept d on e.empid=d.empid Example of left outer join: select * from emp e left outer join dept d on e.empid=d.empid Example of right outer join: select * from emp e right outer join dept d on e.empid=d.empid

https://www.essentialsql.com/what-is-the-difference-between-an-inner-and-outer-join/

nner Join Inner join is the most common type of Join which is used to combine the rows from two tables and create a result set containing only such records that are present in both the tables based on the joining condition (predicate). where as Outer Join Outer Join, on the other hand, will return matching rows from both tables as well as any unmatched rows from one or both the tables (based on whether it is single outer or full outer join respectively).