Why can I not see a table I own inside a procedure

Question

I have a procedure owned by user X as follows:
create or replace  procedure ztm_get_debug_level is
  vc_pkg_name  system_parameter.name%TYPE := 'DEBUG_LEVEL_PKG_BASE_KEYS';
  vn_error     services.debug_log_level.debug_level_id%TYPE := 30;
  v_debugLevel   system_parameter.number_value%TYPE;
  function get_owner return varchar2 is
    cursor c1 is
    select owner from all_tables where table_name = 'SYSTEM_PARAMETER';
    v_Ret_Val VARCHAR2(30);
  BEGIN
    OPEN C1;
    FETCH C1 INTO v_Ret_Val;
    CLOSE C1;
    RETURN v_Ret_Val;
  END;
begin
  DBMS_OUTPUT.PUT_LINE('AAAA - ' || get_owner);
  select s.number_value
  into   v_debugLevel
  from   system_parameter  s
  where  s.name = vc_pkg_name;
  DBMS_OUTPUT.PUT_LINE('BBBB');
exception
  when no_data_found then
    NULL;
  when others then
   DBMS_OUTPUT.PUT_LINE('p_get_debug_level.WHEN OTHERS');
   raise;
end;
Table system_parameter is owned by user X.
When I execute I get:
TESTSSG.SUBSCRIPTION.87> exec ztm_get_debug_level
AAAA - X
p_get_debug_level.WHEN OTHERS
BEGIN ztm_get_debug_level; END;
ERROR at line 1:
ORA-00942: table or view does not exist
ORA-06512: at "SUBSCRIPTION.ZTM_GET_DEBUG_LEVEL", line 32
ORA-06512: at line 1
When I run the query outside the procedure as user X I get a row.
Any ideas?
FYI, there are no public sysnonyms.
DB version: 11.2.0.3.0
Thanks,
Thomas

Answer 1

Thanks Frank,
SYSTEM_PARAMETER is a table owned by X.  If I qualify the select statement by adding the owner it works, but of course I do not want to do that.  Here is the DDL for creating SYSTEM_PARAMETER:
create table SYSTEM_PARAMETER
  name         VARCHAR2(256) not null,
  date_value   DATE,
  number_value NUMBER,
  string_value VARCHAR2(512),
  comments     VARCHAR2(512)
alter table SYSTEM_PARAMETER add constraint PK_SYSTEM_PARAMETER primary key (NAME);
Again, if I rewrite the procedure to the following (only difference is the red X.), it works:
create or replace  procedure ztm_get_debug_level is
  vc_pkg_name  system_parameter.name%TYPE := 'DEBUG_LEVEL_PKG_BASE_KEYS';
  vn_error     services.debug_log_level.debug_level_id%TYPE := 30;
  v_debugLevel   system_parameter.number_value%TYPE;
  function get_owner return varchar2 is
    cursor c1 is
    select owner from all_tables where table_name = 'SYSTEM_PARAMETER';
    v_Ret_Val VARCHAR2(30);
  BEGIN
    OPEN C1;
    FETCH C1 INTO v_Ret_Val;
    CLOSE C1;
    RETURN v_Ret_Val;
  END;
begin
  DBMS_OUTPUT.PUT_LINE('AAAA - ' || get_owner);
  select s.number_value
  into   v_debugLevel
  from   X.system_parameter  s
  where  s.name = vc_pkg_name;
  DBMS_OUTPUT.PUT_LINE('BBBB');
exception
  when no_data_found then
    NULL;
  when others then
   DBMS_OUTPUT.PUT_LINE('p_get_debug_level.WHEN OTHERS');
   raise;
end;
This procedure exists in 4 other environments where there are no issues.  It can't be a privileges issue as the table is owned by user X and as you can see by the lookup (which was added for debug) against ALL_TABLES the owner is clearly X.  So, why can X not select from it's own table unless we include the owner?
Thanks,
Thomas