JOIN VIA RANGE OF MULTIPLE KEY COLUMNS 
JOIN VIA°RANGE°OF°MULTIPLE KEY°COLUMNS is a search strategy of the SQL Optimizer for joins.
This search strategy can be used if the join columns can be combined as the initial part of the key of the new table. This key consists of multiple columns.
Within the key range, the system accesses the table rows in the new table sequentially.
See also:
Search strategies for Joins