Problem with using ALL_SEQUENCES in a function

Question

Hi all. I want to create a function that returns the current value of an Oracle sequence. My function looks like this:
function getSequenceCurrentValue(sequenceName varchar2) return integer is
sequenceLastNumber integer;
begin
select tb_all_sequences.LAST_NUMBER into sequenceLastNumber
from sys.ALL_SEQUENCES tb_all_sequences
where tb_all_sequences.SEQUENCE_NAME = sequenceName;
return sequenceLastNumber;
end;
For example there are two users in my database: User1 and User2.
User1 owns Seq11 and Seq12
User2 owns Seq21 and Seq22.
User1 has the privilege to access Seq21 and Seq22.
But when I try to use my function to get the last number of Seq21 or Seq22 when logged as User1 the function returns NULL.
When I try to get the last number of Seq11 or Seq12 when logged as User1 the function works.
Does anyone have any ideas why the function does not work with the sequences which are not owned by the logged user? Oracle docs say ALL_SEQUENCES 'describes all sequences accessible to the user'.

Answer 1

With direct privileges it is not a problem:
SQL> create user user1 identified by user1
  2  /
Gebruiker is aangemaakt.
SQL> grant create session, create procedure, create sequence to user1
  2  /
Toekennen is geslaagd.
SQL> grant select on all_sequences to user1
  2  /
Toekennen is geslaagd.
SQL> create user user2 identified by user2
  2  /
Gebruiker is aangemaakt.
SQL> grant create session, create sequence to user2
  2  /
Toekennen is geslaagd.
SQL> conn user1/user1
Verbonden.
SQL> create function getSequenceCurrentValue(sequenceName varchar2) return integer
  2  is
  3    sequenceLastNumber integer;
  4  begin
  5    select tb_all_sequences.LAST_NUMBER into sequenceLastNumber
  6    from sys.ALL_SEQUENCES tb_all_sequences
  7    where tb_all_sequences.SEQUENCE_NAME = sequenceName;
  8    return sequenceLastNumber;
  9  end;
10  /
Functie is aangemaakt.
SQL> create sequence seq11 start with 1 increment by 1 nocache
  2  /
Reeks is aangemaakt.
SQL> create sequence seq12 start with 1 increment by 1 nocache
  2  /
Reeks is aangemaakt.
SQL> conn user2/user2
Verbonden.
SQL> create sequence seq21 start with 1 increment by 1 nocache
  2  /
Reeks is aangemaakt.
SQL> create sequence seq22 start with 1 increment by 1 nocache
  2  /
Reeks is aangemaakt.
SQL> grant select on seq21 to user1
  2  /
Toekennen is geslaagd.
SQL> grant select on seq22 to user1
  2  /
Toekennen is geslaagd.
SQL> conn user1/user1
Verbonden.
SQL> select getsequencecurrentvalue('SEQ11') seq11
  2       , getsequencecurrentvalue('SEQ12') seq12
  3       , getsequencecurrentvalue('SEQ21') seq21
  4       , getsequencecurrentvalue('SEQ22') seq22
  5    from dual
  6  /
     SEQ11      SEQ12      SEQ21      SEQ22
         1          1          1          1
1 rij is geselecteerd.Regards,
Rob.