An index scan may be used for a query
containing a single MIN() or MAX() function in the select list
if an index exists on the column the function is applied to, and
if the function is applied to the first column in the index.
The index scan is considered for queries with or without predicates,
including MIN() or MAX() on a join column in a nested loop join,
provided the MIN() or MAX() is applied to a column in the outermost table.
An index scan plan for MIN() or MAX() cannot be considered for
queries in which there is an expression, an ORDER BY or GROUP BY clause,
or where tables are joined using the sort/merge join method.
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