What different of iner joint & outer joint with example
Answer Posted / nusrath sultana
Inner join:fetch the data when matched,similar to equi join.
Outer join:fetch the data matched as well as some unmatched
data.
there are three types of outer join :
1)left outer join:it will fetch the data when matches in two
or more relation and the unmatched data from the left
relation is also selected.
SQL>SELECT E.ENAME,E1.COMM FROM EMP E LEFT OUTER JOIN EMP E1
ON E.EMPNO=E1.EMPNO;
2)right outer join:it will fetch the data when matches in
two or more relation and the unmatched data from the right
relation also selected.
SQL>SELECT E.ENAME,E1.COMM FROM EMP E RIGHT OUTER JOIN EMP
E1 ON E.EMPNO=E1.EMPNO;
3)full outer join:it will fetch the data when matches in two
or more relation and the unmatched data from the BOTH
relations are also selected.
SQL>SELECT E.ENAME,E1.COMM FROM EMP E FULL OUTER JOIN EMP E1
ON E.EMPNO=E1.EMPNO;
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