What is the difference between Outer join and Full outer join?

Answer Posted / a g srikanth

Amongh outer joins there are three types
1)Left outer join
2)Right outer join
3)Full outer join

Left outer join: In this join the (+) sign is given with
the table to the left of the equal to sign

i.e emp.deptid(+)=dept.deptid

here we are seeking blank columns from the left table i.e.
emp if no matching columns are there in the right table i.e
dept

Right outer join: In this join the (+) sign is given with
the table to the right of the equal to sign

i.e emp.deptid=dept.deptid (+)

here we are seeking blank columns from the right table i.e.
dept if no matching columns are there in the left table i.e
emp.

NOTE:scott.emp and dept values do not give any rows for
right outer joins, for right outer join, assume that there
is some employee in emp table who is not yet assigned any
department number.

Full outer join:in this type of join we force blanks if any
from both the tables

SELECT *
FROM emp
FULL OUTER JOIN dept
ON emp.Deptid = dept.Deptid

Is This Answer Correct ?    5 Yes 6 No



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