Re: initrans for table

From: Harry Sheng <hsheng_at_innovance.com>
Date: Thu, 10 Oct 2002 09:02:13 -0400
Message-ID: <jYep9.15184$H67.68691@tor-nn1.netcom.ca>

Ok, I may misunderstand the mechanism of pre-allocating ITL in block header. If I just create the table, and dump the blocks before I insert any records into
the table, there will be only one ITL entry is each table block.

I have to insert some records into the table, then the table blocks with data
record in will have the ITL entries I expected. But the blocks without any data records in still have only one ITL entry, at least it is as I saw from the
dump file.

Here is how I dump the blocks:

create table initrans8 ( attr1 number(10), attr2 varchar2(255), attr3 char(32) ) initrans 8 storage (freelists 4) ;
select header_file, header_block, blocks, extents from dba_segments where segment_name='INITRANS8';

HEADER_FILE HEADER_BLOCK BLOCKS EXTENTS

---------------------- ----------- --------- --- 8 18577 5 1 3. alter system dump datafile 8 block min 18577 block max 18582

Here are the dump-ed block headers:

Start dump data blocks tsn: 7 file#: 8 minblk 18577 maxblk 18582 buffer tsn: 7 rdba: 0x02004891 (8/18577) scn: 0x0000.00089565 seq: 0x02 flg: 0x00 tail: 0x95651002 frmt: 0x02 chkval: 0x0000 type: 0x10=DATA SEGMENT HEADER - UNLIMITED

Extent Control Header

  Extent Header:: spare1: 0      space2: 0      #extents: 1      #blocks: 4
                  last map  0x00000000  #maps: 0      offset: 4128
      Highwater::  0x02004892  ext#: 0      blk#: 0      ext size: 4

#blocks in seg. hdr's freelists: 0
#blocks below: 0

mapblk 0x00000000 offset: 0

                   Unlocked
     Map Header:: next  0x00000000  #extents: 1    obj#: 13168  flag:

0x40000000
Extent Map

0x02004892 length: 4

nfl = 4, nfb = 1 typ = 1 nxf = 0

  SEG LST:: flg: UNUSED lhd: 0x00000000 ltl: 0x00000000
  SEG LST:: flg: UNUSED lhd: 0x00000000 ltl: 0x00000000
  SEG LST:: flg: UNUSED lhd: 0x00000000 ltl: 0x00000000
  SEG LST:: flg: UNUSED lhd: 0x00000000 ltl: 0x00000000
  SEG LST:: flg: UNUSED lhd: 0x00000000 ltl: 0x00000000

buffer tsn: 7 rdba: 0x02004892 (8/18578) scn: 0x0000.00089559 seq: 0x01 flg: 0x02 tail: 0x95590601 frmt: 0x02 chkval: 0x0000 type: 0x06=trans data

Block header dump: 0x02004892
Object id on Block? Y
seg/obj: 0x336e csc: 0x00.7fcd9 itc: 2 flg: O typ: 1 - DATA

fsl: 0 fnx: 0x0 ver: 0x01

 Itl           Xid                  Uba         Flag  Lck        Scn/Fsc

0x01 xid: 0x0004.04d.00000123 uba: 0x00802853.003b.09 --U- 1 fsc 0x0000.00089559
0x02 xid: 0x0005.00c.00000128 uba: 0x00c015b3.003d.07 --U- 1 fsc 0x0000.00089557

data_block_dump

tsiz: 0x1fa0
hsiz: 0x16
pbl: 0x018a909c
bdba: 0x02004892

flag=-----------
ntab=1
nrow=2

buffer tsn: 7 rdba: 0x02004894 (8/18580) scn: 0x0000.0003334b seq: 0x02 flg: 0x00 tail: 0x334b0602 frmt: 0x02 chkval: 0x0000 type: 0x06=trans data

Block header dump: 0x02004894
Object id on Block? Y
seg/obj: 0x1a41 csc: 0x00.3334b itc: 1 flg: - typ: 1 - DATA

fsl: 0 fnx: 0x0 ver: 0x01

 Itl           Xid                  Uba         Flag  Lck        Scn/Fsc

0x01 xid: 0x0003.011.0000007a uba: 0x01000503.0018.04 C--- 0 scn 0x0000.0003334a

data_block_dump

tsiz: 0x1fb8
hsiz: 0x2c
pbl: 0x018a9084
bdba: 0x02004894

flag=-----------
ntab=1
nrow=13

buffer tsn: 7 rdba: 0x02004895 (8/18581) scn: 0x0000.00033365 seq: 0x02 flg: 0x00 tail: 0x33650602 frmt: 0x02 chkval: 0x0000 type: 0x06=trans data

Block header dump: 0x02004895
Object id on Block? Y
seg/obj: 0x1a41 csc: 0x00.33365 itc: 1 flg: - typ: 1 - DATA

fsl: 0 fnx: 0x0 ver: 0x01

 Itl           Xid                  Uba         Flag  Lck        Scn/Fsc

0x01 xid: 0x0007.008.0000006b uba: 0x00802d89.0018.2f C--- 0 scn 0x0000.00033364

data_block_dump

tsiz: 0x1fb8
hsiz: 0x2c
pbl: 0x018a9084
bdba: 0x02004895

flag=-----------
ntab=1
nrow=13
frre=-1

buffer tsn: 7 rdba: 0x02004896 (8/18582) scn: 0x0000.0005f679 seq: 0x02 flg: 0x00 tail: 0xf6791002 frmt: 0x02 chkval: 0x0000 type: 0x10=DATA SEGMENT HEADER - UNLIMITED

Extent Control Header

  Extent Header:: spare1: 0      space2: 0      #extents: 1      #blocks: 4
                  last map  0x00000000  #maps: 0      offset: 4128
      Highwater::  0x02004897  ext#: 0      blk#: 0      ext size: 4

#blocks in seg. hdr's freelists: 0
#blocks below: 0

mapblk 0x00000000 offset: 0

                   Unlocked
     Map Header:: next  0x00000000  #extents: 1    obj#: 13167  flag:

0x40000000
Extent Map

0x02004897 length: 4

nfl = 1, nfb = 1 typ = 1 nxf = 0
SEG LST:: flg: UNUSED lhd: 0x00000000 ltl: 0x00000000 End dump data blocks tsn: 7 file#: 8 minblk 18577 maxblk 18582

"Jonathan Lewis" <jonathan_at_jlcomp.demon.co.uk> wrote in message news:ao28fv$2g$1$8302bc10_at_news.demon.co.uk...

>
> It would be helpful if you included the relevant
> section of your dump file to prove your point.
>
> It seems MOST unlikely that you have a port
> of Oracle with such a dramatically obvious
> error that no-one has discovered for a couple
> of years.
>
> --
> Regards
>
> Jonathan Lewis
> http://www.jlcomp.demon.co.uk
>
> Next Seminar dates:
> (see http://www.jlcomp.demon.co.uk/seminar.html )
>
> ____USA__________November 7/9   (Detroit)
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>
> The Co-operative Oracle Users' FAQ
> http://www.jlcomp.demon.co.uk/faq/ind_faq.html
>
>
>
>
>
> Harry Sheng wrote in message ...
> >Oracle8i on Solaris8
> >
> >I create a table with initrans set to 4.
> >But if I dump some table blocks and check the ITL entries,
> >there is only one entry unless I have active transactions.
> >
> >I expected 4 ITL entries pre-allocated in each block head.
> >
> >
> >
>
>

Received on Thu Oct 10 2002 - 08:02:13 CDT