Diff bw SQLERRM and DBMS_ UTILITY. FORMAT_ CALL_ STACK

Question

Dear One and all,
In recent times i read some where using DBMS_UTILITY.FORMAT_CALL_STACK is the suitable alternative instead of using SQLERRM is it so ? Could any one one tell me what is the exact difference b/w both with simple program / and how to use DBMS_UTILITY.FORMAT_CALL_STACK in PL/SQL programming ..

Answer 1

I think we are talking about different things.
The example in the documentation uses RAISE to create the exception. It does not use RAISE after the WHEN OTHERS.
The example does RAISE followed by WHEN OTHERS.
I say we need to do WHEN OTHERS followed by RAISE.
I compiled the example and ran it. Here is what happens at the end:set serveroutput on
exec Top_With_Logging();
anonymous block completed
Error_Stack...
ORA-01476: divisor is equal to zero
Error_Backtrace...
ORA-06512: at "STEW.P0", line 4
ORA-06512: at "STEW.P1", line 3
ORA-06512: at "STEW.P2", line 3
ORA-06512: at "STEW.P3", line 3
ORA-06512: at "STEW.P4", line 2
ORA-06512: at "STEW.P5", line 2
ORA-06512: at "STEW.TOP_WITH_LOGGING", line 6
----------Do you see the line anonymous block completed? That means that the anonymous block received no exception from Top_With_Logging, because Top_With_Logging "swallowed" the exception by handling it and not re-raising it.
As a result, if you do any work in a PL/SQL block and then call Top_With_Logging, the work will not be rolled back. Consider:s> delete from t
1 rows deleted.
s> commit
commited.
s> begin
insert into t values(1);
top_naive();
end;
Error starting at line 3 in command:
begin
insert into t values(1);
top_naive();
end;
Error report:
ORA-01476: divisor is equal to zero
ORA-06512: at "STEW.P0", line 4
ORA-06512: at "STEW.P1", line 3
ORA-06512: at "STEW.P2", line 3
ORA-06512: at "STEW.P3", line 3
ORA-06512: at "STEW.P4", line 2
ORA-06512: at "STEW.P5", line 2
ORA-06512: at "STEW.TOP_NAIVE", line 3
ORA-06512: at line 3
01476. 00000 -  "divisor is equal to zero"
*Cause:   
*Action:
s> commit
commited.
s> select * from t
no rows selectedThe insert was rolled back. Now call top_with_logging:s> begin
insert into t values(1);
top_with_logging();
end;
anonymous block completed
s> commit
commited.
s> select * from t
X
1The insert was not rolled back. Swallowing the exception changes the way Oracle behaves in a very important way, to the detriment of data integrity.