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So confusing Oracle left join

Starting with Oracle9i, the confusing outer join syntax using the ‘(+)’ notation has been superseded by ISO 99 outer join syntax.  As we know, there are three types of outer joins, left, right, and full outer join.  The purpose of an outer join is to include non-matching rows, and the outer join returns these missing columns as NULL values. 
Let’s review the syntax differences between these variations in join syntax:
Left outer join:  Oracle8i
select
   last_name,
   department_name
from
   employees e,
   departments d
where
   e.department_id = d.department_id(+);
Left outer join:  Oracle9i
select
   last_name,
   department_name
from
   employees e
left outer join
   departments d
on
   e.department_id = d.department_id;

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