PLS-00318: type "string" is malformed because it is a non-REF mutually recursive type
Cause: A type-declaration such as: -- non-REF recursive type type t is record (a t); or -- non-REF mutually dependent types type t1; type t2 is record (a t1); type t1 is record (a t2); was entered.
Action: Use another type to remove the recursion.