A FULL OUTER JOIN Join combines Left outer join and right outer join.it will display the rows from either tables when the condtions are met and returns null when there is no match found.
Ex:
Left Table(emp Table)
------------------------------------------------------------------------
empID FirstName LastName UserName
------------------------------------------------------------------------
1 John Miller John
2 Steve Jobs Steve
3 Billgates john Billgates
4 Ozzy Ozzbourne Ozzy
5 Homer Gain Homer
--------------------------------------------------------------------------
Right Table(dept Table)
------------------------------------------------------
empID DeptName
------------------------------------------------------
1 IT
2 Networking
3 Networking
4 Networking
12 Admin
------------------------------------------------------
Query :
SELECT * FROM emp AS e
FULL JOIN dept AS d
ON e.empid = d.empid
result:
empID FirstName LastName UserName IndividualId AccessLevel
1 John Miller John 1 IT
2 Steve Jobs Steve 2 Networking
3 Billgates john Billgates 3 Networking
4 Ozzy Ozzbourne Ozzy 4 Networking
5 Homer Gain Homer NULL NULL
NULL NULL NULL NULL 12 Admin
Ex:
Left Table(emp Table)
------------------------------------------------------------------------
empID FirstName LastName UserName
------------------------------------------------------------------------
1 John Miller John
2 Steve Jobs Steve
3 Billgates john Billgates
4 Ozzy Ozzbourne Ozzy
5 Homer Gain Homer
--------------------------------------------------------------------------
Right Table(dept Table)
------------------------------------------------------
empID DeptName
------------------------------------------------------
1 IT
2 Networking
3 Networking
4 Networking
12 Admin
------------------------------------------------------
Query :
SELECT * FROM emp AS e
FULL JOIN dept AS d
ON e.empid = d.empid
result:
empID FirstName LastName UserName IndividualId AccessLevel
1 John Miller John 1 IT
2 Steve Jobs Steve 2 Networking
3 Billgates john Billgates 3 Networking
4 Ozzy Ozzbourne Ozzy 4 Networking
5 Homer Gain Homer NULL NULL
NULL NULL NULL NULL 12 Admin
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