Cause: A type-declaration such as: — a
non-REF recursive type, for example: type t is record (a t); or — non-REF
mutually dependent types, for example: type t1; type t2 is record (a t1); type
t1 is record (a t2); was performed. In these examples, the type is malformed
because it participates in a mutually recursive non-REF relationship with
itself and possibly other types.
Action: Use another type to remove the
recursion.

Relared Errors:
PLS-00319:
subquery in an IN or NOT IN clause must contain exactly one
column
PLS-00320: the
declaration of the type of this expression is incomplete or
malformed
PLS-00321:
expression `string` is inappropriate as the left hand side of an
assignmen
PLS-00322:
declaration of a constant `string` must contain an initialization
assignme
PLS-00323:
subprogram or cursor `string` is declared in a package specification
and m
PLS-00324:
cursor attribute may not be applied to non-cursor
`string`
PLS-00325:
non-integral numeric literal string is inappropriate in this
context
PLS-00326: IN
clause must contain same number of expressions as subquery
PLS-00327:
string is not in SQL scope here
PLS-00328: A
subprogram body must be defined for the forward declaration of
string.