A cursor variable is associated with different statements at run time,
which can hold different values at run time. Static cursors can only be
associated with one run time query. A cursor variable is reference type
(like a pointer in C).
Declaring a cursor variable:
TYPE type_name IS REF CURSOR RETURN return_type type_name is the
name of the reference type,return_type is a record type indicating the
types of the select list that will eventually be returned by the cursor
variable.