A joined table represents a join between two table references
    specified in the FROM clause.

    There are two types of joined tables:

    o  Qualified join-syntax contains either an implicit or explicit
       predicate

    o  Cross join-syntax does not contain a predicate

    A table can be joined to itself or joined to other tables. When
    an outer join is specified in the joined-table expression, you
    can use the parentheses to explicitly define the join order.
    If only inner or cross joins are specified in the joined-table
    expression, the use of parentheses does not affect the join
    order. SQL tries all possible join orders to find the most
    efficient order for the query. If outer joins are specified in
    the joined-table expression, the join order is determined first
    by any existing parentheses and then by the left-to-right rule.

    The table or correlation names specified in the joined-table
    expression can be referenced by the outer select expression.