ORA-22908: reference to NULL table value
Cause: The evaluation of the THE subquery or nested table column resulted in a NULL value implying a NULL table instance. The THE subquery or nested table column must identify a single non-NULL table instance
Action: Ensure that the evaluation of the THE subquery or nested table column results in a single non-null table instance. If happening in the context of an insert statement where the THE subquery is the target of an insert, then ensure that an empty nested table instance is created by updating the nested table column of the parent table's row specifying an empty nested table constructor
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