In this post I will brief you Oracle 12c limitations for outer joins.  You can only put the outer join operator on one side of the join not both. If you will try to put the outer join operator on both sides of join, then you will get an error. An example is given below:

Select e.name, b.bonus_amt
 from emp e, bonus b
 where e.empno(+) = b.empno(+);

The above query will raise ORA-01468 error. Another example is given below for outer join using OR operator:

Select e.name, b.bonus_amt
 from emp e, bonus b
 where e.empno(+) = b.empno(+)
 or e.empno = 100;

The above query will also raise an error ORA-01719, which will tell you that outer join operator (+) is not allowed with OR or IN.

Vinish Kapoor

An Oracle Apex Consultant, Oracle ACE, and founder of foxinfotech.in and orclqa.com a question and answer forum for developers.

Leave a Reply