Message Oracle PLS-00316 - PL/SQL TABLEs must use a single index

ERRORPL/SQL TABLEs must use a single index
CAUSEIn the INDEX BY clause of a PL/SQL table declaration, a composite primary key was specified. PL/SQL tables must have a simple, unnamed primary key of a binary integer or VARCHAR2 type.
ACTIONUse one of the supported key types in the INDEX BY clause.