Join Types – inner, left outer, right outer and outer join

Inner Join:

This join type will allow only the matched rows in the result and unmatched rows of both left and right side of the relation are excluded.

Left Outer Join:

This join type will allow the matched rows and unmatched rows of left side relation in the result along with null values for the columns of right side relation.

Left outer join represents deficiency on the right relation.

Right Outer Join:

This join type will allow the matched rows unmatched rows of right side relation in the result along with null values for the columns of left side relation.

Right outer join represent deficiency in left side relation.

Full Outer or Outer Join:

This join type will allow the matched rows and unmatched rows of both left and right relation along with null values for the respective attributes in the result.