bool oci_field_is_null ( resource stmt, mixed field )
oci_field_is_null() returns TRUE if field
field from the statement is
NULL. Parameter field could be a field's index
or a field's name (uppercased).
In PHP versions before 5.0.0 you must use ocicolumnisnull() instead.
This name still can be used, it was left as alias of
oci_field_is_null() for downwards compatability.
This, however, is deprecated and not recommended.