Using a Right Outer Join

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A right outer join retrieves all rows from the right table in a join, and only those rows from the left table that match the search condition specified in the ON clause. The following right outer join retrieves a list of rivers and their countries of origin, but also reports those countries that are not the source of any river:

EXEC SQL
DECLARE RIVSOURCE CURSOR FOR
SELECT R.RIVER, C.COUNTRY
FROM RIVERS.R RIGHT JOIN COUNTRIES C ON C.COUNTRY = R.SOURCE
ORDER BY C.COUNTRY;
Tip: Most right outer joins can be rewritten as left outer joins by reversing the order in which tables are listed.