SQL> conn ALM/***@DEV
Connected.
SQL> with
  2  function f(p number) return varchar2 deterministic is
  3     v number;
  4  begin
  5     with
  6     x as (select 1 a, 1 b from dual where 1 = 0),
  7     y as (select a from x start with x.b = 0 connect by prior x.a = x.b),
  8     z as (select * from y)
  9     select null into v from z;
 10     return null;
 11  end f;
 12  select f(1) from dual
 13  /
SP2-0642: SQL*Plus internal error state 2147, context 0:0:0
Unsafe to proceed
SQL> select * from v$version
  2  /

BANNER                                                                               CON_ID
-------------------------------------------------------------------------------- ----------
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production              0
PL/SQL Release 12.2.0.1.0 - Production                                                    0
CORE    12.2.0.1.0      Production                                                        0
TNS for Linux: Version 12.2.0.1.0 - Production                                            0
NLSRTL Version 12.2.0.1.0 - Production                                                    0

ORA-24374: не сделаны определения перед извлечением или выполнением с извлечением

SQL> with
  2  function f(p number) return varchar2 deterministic
  3  as
  4     v number;
  5  begin
  6     with
  7     z as (select 1 a from dual where 1=0)
  8     select null into v from z;
  9     return null;
10  end f;
11  select f(1) from dual
12  /
SP2-0642: SQL*Plus internal error state 2147, context 0:0:0
Unsafe to proceed
SQL> with
  2  function f(p number) return varchar2 deterministic
  3  as
  4     v number;
  5  begin
  6     with
  7     z as (select 1 a from dual where 1=0)
  8     select null into v from z;
  9     return null;
10  exception
11     when no_data_found then
12             return null;
13  end f;
14  select f(1) from dual
15  /

F(1)
--------------------------------------------------------------------------------