RE: How can I get the BBED password?
- From: "Guerra, Abraham J" <AGUERRA@xxxxxxxxx>
- To: <lex.de.haan@xxxxxxxxxxxxxx>
- Date: Wed, 13 Apr 2005 13:30:19 -0500
Hello Lex,
These are the dumps:
Dump1: I inserted 5 rows to a table with only 1 filed (number) and
deleted the middle three rows. See how the offsets start from the
bottom of the block:
0x12:pri[0] offs=3D0x1f9a
0x14:pri[1] offs=3D0x1f94
0x16:pri[2] offs=3D0x1f8e
0x18:pri[3] offs=3D0x1f88
0x1a:pri[4] offs=3D0x1f82
block_row_dump:
tab 0, row 0, @0x1f9a
tl: 6 fb: --H-FL-- lb: 0x0 cc: 1
col 0: [ 2] c1 02
tab 0, row 1, @0x1f94
tl: 2 fb: --HDFL-- lb: 0x2
tab 0, row 2, @0x1f8e
tl: 2 fb: --HDFL-- lb: 0x2
tab 0, row 3, @0x1f88
tl: 2 fb: --HDFL-- lb: 0x2
tab 0, row 4, @0x1f82
tl: 6 fb: --H-FL-- lb: 0x0 cc: 1
col 0: [ 2] c1 06
Now dump2, when I inserted 1000 rows, slots 1,2 and 3 were reused but
the space offset was not:
0xe:pti[0] nrow=3D660 offs=3D0
0x12:pri[0] offs=3D0x1f9a
0x14:pri[1] offs=3D0xdfb
0x16:pri[2] offs=3D0xdf4
0x18:pri[3] offs=3D0xded
0x1a:pri[4] offs=3D0x1f82
0x1c:pri[5] offs=3D0x1f7c
0x1e:pri[6] offs=3D0x1f76
0x20:pri[7] offs=3D0x1f70
0x22:pri[8] offs=3D0x1f6a
0x24:pri[9] offs=3D0x1f64
0x26:pri[10] offs=3D0x1f5e
0x28:pri[11] offs=3D0x1f58
...
It was until it got to the 656 insert that it started to reuse the
record slots deleted but it did not reuse the record space...
SQL> select * from foo where rownum < 10;
A1
----------
1
656
657
658
5
1
2
3
4
So, my question is: what happened to space from 0x1f94 to 0x1f88??? I
wanted to use bbed to see what kind of data is there...
Thanks.
Abraham
-----Original Message-----
From: Lex de Haan [mailto:lex.de.haan@xxxxxxxxxxxxxx]=20
Sent: Wednesday, April 13, 2005 11:02 AM
To: Guerra, Abraham J
Cc: lex.de.haan@xxxxxxxxxxxxxx; matthewp@xxxxxxxxxx;
tanel.poder.003@xxxxxxx; oracle-l@xxxxxxxxxxxxx
Subject: RE: How can I get the BBED password?
please show me your tests, and the results. until proven otherwise, I
simply don't believe it. Oracle does garbage collection at the block
level.
in other words, something else is going on...
just out of curiosity, did you commit your changes?
and again, a utility like BBED is not going to help you any further.
formatted block dumps typically don't ly about where rows are stored :-)
Lex.
> Hello Lex,
>
> I've been using the 'alter system dump' but I have seen that the
offset
> of the deleted row is never reused in my tests... =3D20
>
> Instead of using deleted space it jumps to the next block when needing
> new space. This is Oracle 9 I'm doing the testing with.
>
> Thanks for your observations.
>
> Abraham
>
> -----Original Message-----
> From: Lex de Haan [mailto:lex.de.haan@xxxxxxxxxxxxxx]=3D20
> Sent: Wednesday, April 13, 2005 10:10 AM
> To: Guerra, Abraham J
> Cc: matthewp@xxxxxxxxxx; tanel.poder.003@xxxxxxx;
oracle-l@xxxxxxxxxxxxx
> Subject: RE: How can I get the BBED password?
>
>
> This is plain wrong. Oracle will do garbage collection at due time.
that
> is, if there is not enough free space left "in the middle" but Oracle
> knows the total free space for the block is "good enough"...
>
> and for this type of investigations, you don't need BBED. just "alter
> system dump ..." will do the trick.
>
> cheers,
> Lex.
>
>
>> Thanks to all that have responded...
>>
>> Well, something that I've noticed with regular dumps is that when you
>> update a null column in a record, the whole row is migrated within
the
>> block to a new location and the space in never reused... I want to
use
>> bbed to see if that is true...
>>
>> Thanks again to all,
>>
>> Abraham
>>
>> -----Original Message-----
>> From: oracle-l-bounce@xxxxxxxxxxxxx
>> [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Parker, Matthew
>> Sent: Wednesday, April 13, 2005 2:22 AM
>> To: tanel.poder.003@xxxxxxx; oracle-l@xxxxxxxxxxxxx
>> Subject: RE: How can I get the BBED password?
>>
>>
>> An excellent observation Tanel.
>> Abraham, what exactly are you looking to accomplish? The standard
dump
> =3D3D
>> =3D3D3D
>> utilities of Oracle provide most of what you may be looking for. Out
> of
>> =3D3D3D
>> all the block repairs I have had to do over the years, the only thing
> =3D3D
>> =3D3D3D
>> bbed has provided me is the ability to run a verify on the block I
> have
>> =3D3D3D
>> repaired before I replace the block in the file, since dbv requires
> the
>> =3D3D3D
>> block to be a part of the file, otherwise I find the tool to be less
> =3D3D3D
>> than useful.=3D3D3D20
>>
>> In the world there are about 7 Oracle BDE/RDBMS development people
who
> =3D3D
>> =3D3D3D
>> can edit blocks well and only 1 or 2 others who understand and try to
> =3D3D
>> =3D3D3D
>> edit the redo stream, and in my dealings with most of them they have
> =3D3D3D
>> their own tools because bbed is archaic. The lower end Support
> personnel
>> =3D3D3D
>> who do use bbed, normally do not have the skills or knowledge to edit
> =3D3D
>> =3D3D3D
>> the blocks in the first place.
>>
>> If you are trying to understand block structures, then you should
read
> =3D3D
>> =3D3D3D
>> the documentation and the many papers that are available. There is no
> =3D3D
>> =3D3D3D
>> single source of information that will tell you everything and there
> are
>> =3D3D3D
>> a lot of flags and pointer values that are not documented anywhere
but
> =3D3D
>> =3D3D3D
>> in the code itself. In the last year working on lots of block =3D3D3D
>> corruptions from Linux induced problems, almost every time, the
actual
> =3D3D
>> =3D3D3D
>> people who can edit blocks well, had to reference the code for =
=3D3D3D
>> determination of some of the flags. It is just the reality that =
=3D3D3D
>> everyone, can't know everything.
>> So back to the question, what are you truly trying to find out? The
> tool
>> =3D3D3D
>> has no training mode and it does not document the oracle block
> structure
>> =3D3D3D
>> for you.=3D3D3D20
>>
>>
>> -----Original Message-----
>> From: oracle-l-bounce@xxxxxxxxxxxxx =3D3D3D
>> [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Tanel =
P=3D3D3DF5der
>> Sent: Tuesday, April 12, 2005 3:24 PM
>> To: oracle-l@xxxxxxxxxxxxx
>> Subject: Re: How can I get the BBED password?
>>
>> Hi,
>>
>> It's a really trivial task to find the password if you think about it
> a
>> =3D3D3D
>> bit,=3D3D3D20
>> that's why I think it's everyone's own responsibility to find it out
> if
>> =3D3D3D
>> you=3D3D3D20
>> actually need the utility. Also, the more people start messing up
>> their=3D3D3D20
>> databases with bbed, the more likely will Oracle remove it from =3D3D
>> next=3D3D3D20
>> distribution at all or encrypt the password or similar...
>>
>> Tanel.
>>
>> ----- Original Message -----=3D3D3D20
>> From: "Guerra, Abraham J" <AGUERRA@xxxxxxxxx>
>> To: <oracle-l@xxxxxxxxxxxxx>
>> Sent: Tuesday, April 12, 2005 10:39 PM
>> Subject: How can I get the BBED password?
>>
>>
>>> Hello all,
>>>
>>> I'm trying to dump some blocks with bbed. It asks for a password.
>>> According to Steve Adams, if I used strings on bbed I should find
the
>>> password in 30 seconds... It's been 3 days... anybody know how to
> find
>>> it?
>>>
>>> TIA.
>>>
>>> Abraham Guerra
>>> American Family Insurance
>>> Oracle DBA
>>> --
>>> //www.freelists.org/webpage/oracle-l=3D3D3D20
>>
>> --
>> //www.freelists.org/webpage/oracle-l
>> --
>> //www.freelists.org/webpage/oracle-l
>> --
>> //www.freelists.org/webpage/oracle-l
>>
> --
> //www.freelists.org/webpage/oracle-l
>
--
//www.freelists.org/webpage/oracle-l
Other related posts:
