LAST_VALUE

LAST_VALUE ( <value-expression> )  OVER <window-specification>

LAST_VALUE returns the evaluation of the <value expression> from the last row that qualifies for the aggregate.

Null Treatment Option	Effect
LAST_VALUE(x) IGNORE NULLS OVER <window-specification>	Returns last non null value of x in <window-specification>
LAST_VALUE(x) RESPECT NULLS OVER <window-specification>	Returns last value, including null of x in <window-specification>
LAST_VALUE(x) OVER <window-specification>	Returns last value, including null of x in <window-specification>