Corrpupt Data File - Mailing list pgsql-bugs

Hi,

    I have a postgres data base that is probably about 2gigs in size
spread across a couple of tables.  The orders table is about 500megs in
size and is mostly writes.

    When running "select count(1) from orders" on the database this
evening, the DB responded with "ERROR:  Invalid page header in block 57879
of orders".  After doing a bunch of reading online, I downloaded
pg_filedump and ran it against the offending block with these results:

*****************************************************************
* PostgreSQL File/Block Formatted Dump Utility - Version 1.1
*
* File: 309928249
* Options used: -R 57879
*
* Dump created on: Thu Feb 26 01:19:09 2004
*****************************************************************

Block 57879 ******************************************************
<Header> -----
 Block Offset: 0x1c42e000         Offsets: Lower       3 (0x0003)
 Block: Size 16384  Version   24            Upper    10679 (0x29b7)
 LSN:  logid 808988729 recoff 0x00000037      Special    79 (0x004f)
 Items:   -4                   Free Space: 10676
 Length (including item array): 24

 Error: Invalid header information.

<Data> ------
 Error: Item index corrupt on block. Offset: <-4>.

<Special Section> -----
 Error: Invalid special section encountered.

*** End of Requested Range Encountered. Last Block Read: 57879 ***


The blocks both before and after this block are fine.  (I'll include the
header from one at the end of this message).  I should mention that I am
running postgres 7.3 on AMD-64 hardware with kernel 2.4.25.

deleting the indexes from the table did not help.  Is there a tool or
method that that I could use to simply skip the bad data and at least
recover the good blocks?

Thanks
-Alex

*****************************************************************
* PostgreSQL File/Block Formatted Dump Utility - Version 1.1
*
* File: 309928249
* Options used: -R 57880
*
* Dump created on: Thu Feb 26 01:24:00 2004
*****************************************************************

Block 57880 ******************************************************
<Header> -----
 Block Offset: 0x1c430000         Offsets: Lower     336 (0x0150)
 Block: Size 8192  Version    1            Upper     336 (0x0150)
 LSN:  logid     17 recoff 0x5e6c8704      Special  8192 (0x2000)
 Items:   79                   Free Space:    0
 Length (including item array): 340

<Data> ------
 Item   1 -- Length:  102  Offset: 8088 (0x1f98)  Flags: USED
 Item   2 -- Length:   94  Offset: 7992 (0x1f38)  Flags: USED
 Item   3 -- Length:  120  Offset: 7872 (0x1ec0)  Flags: USED
 Item   4 -- Length:  120  Offset: 7752 (0x1e48)  Flags: USED
 Item   5 -- Length:  120  Offset: 7632 (0x1dd0)  Flags: USED
 Item   6 -- Length:  102  Offset: 7528 (0x1d68)  Flags: USED
 Item   7 -- Length:   95  Offset: 7432 (0x1d08)  Flags: USED
 Item   8 -- Length:  120  Offset: 7312 (0x1c90)  Flags: USED
 Item   9 -- Length:  102  Offset: 7208 (0x1c28)  Flags: USED
 Item  10 -- Length:  102  Offset: 7104 (0x1bc0)  Flags: USED
 Item  11 -- Length:  104  Offset: 7000 (0x1b58)  Flags: USED
 Item  12 -- Length:  104  Offset: 6896 (0x1af0)  Flags: USED
 Item  13 -- Length:  120  Offset: 6776 (0x1a78)  Flags: USED
 Item  14 -- Length:   72  Offset: 6704 (0x1a30)  Flags: USED
 Item  15 -- Length:   72  Offset: 6632 (0x19e8)  Flags: USED
 Item  16 -- Length:  120  Offset: 6512 (0x1970)  Flags: USED
 Item  17 -- Length:   96  Offset: 6416 (0x1910)  Flags: USED
 Item  18 -- Length:  104  Offset: 6312 (0x18a8)  Flags: USED
 Item  19 -- Length:  104  Offset: 6208 (0x1840)  Flags: USED
 Item  20 -- Length:   72  Offset: 6136 (0x17f8)  Flags: USED
 Item  21 -- Length:  120  Offset: 6016 (0x1780)  Flags: USED
 Item  22 -- Length:   96  Offset: 5920 (0x1720)  Flags: USED
 Item  23 -- Length:   72  Offset: 5848 (0x16d8)  Flags: USED
 Item  24 -- Length:   72  Offset: 5776 (0x1690)  Flags: USED
 Item  25 -- Length:   72  Offset: 5704 (0x1648)  Flags: USED
 Item  26 -- Length:  120  Offset: 5584 (0x15d0)  Flags: USED
 Item  27 -- Length:  120  Offset: 5464 (0x1558)  Flags: USED
 Item  28 -- Length:  101  Offset: 5360 (0x14f0)  Flags: USED
 Item  29 -- Length:   72  Offset: 5288 (0x14a8)  Flags: USED
 Item  30 -- Length:   94  Offset: 5192 (0x1448)  Flags: USED
 Item  31 -- Length:  102  Offset: 5088 (0x13e0)  Flags: USED
 Item  32 -- Length:   72  Offset: 5016 (0x1398)  Flags: USED
 Item  33 -- Length:  120  Offset: 4896 (0x1320)  Flags: USED
 Item  34 -- Length:   93  Offset: 4800 (0x12c0)  Flags: USED
 Item  35 -- Length:   72  Offset: 4728 (0x1278)  Flags: USED
 Item  36 -- Length:  120  Offset: 4608 (0x1200)  Flags: USED
 Item  37 -- Length:  102  Offset: 4504 (0x1198)  Flags: USED
 Item  38 -- Length:   94  Offset: 4408 (0x1138)  Flags: USED
 Item  39 -- Length:  101  Offset: 4304 (0x10d0)  Flags: USED
 Item  40 -- Length:  120  Offset: 4184 (0x1058)  Flags: USED
 Item  41 -- Length:  120  Offset: 4064 (0x0fe0)  Flags: USED
 Item  42 -- Length:  103  Offset: 3960 (0x0f78)  Flags: USED
 Item  43 -- Length:  103  Offset: 3856 (0x0f10)  Flags: USED
 Item  44 -- Length:   96  Offset: 3760 (0x0eb0)  Flags: USED
 Item  45 -- Length:  102  Offset: 3656 (0x0e48)  Flags: USED
 Item  46 -- Length:  101  Offset: 3552 (0x0de0)  Flags: USED
 Item  47 -- Length:   72  Offset: 3480 (0x0d98)  Flags: USED
 Item  48 -- Length:   72  Offset: 3408 (0x0d50)  Flags: USED
 Item  49 -- Length:   72  Offset: 3336 (0x0d08)  Flags: USED
 Item  50 -- Length:   72  Offset: 3264 (0x0cc0)  Flags: USED
 Item  51 -- Length:   88  Offset: 3176 (0x0c68)  Flags: USED
 Item  52 -- Length:   72  Offset: 3104 (0x0c20)  Flags: USED
 Item  53 -- Length:   96  Offset: 3008 (0x0bc0)  Flags: USED
 Item  54 -- Length:   95  Offset: 2912 (0x0b60)  Flags: USED
 Item  55 -- Length:   72  Offset: 2840 (0x0b18)  Flags: USED
 Item  56 -- Length:  109  Offset: 2728 (0x0aa8)  Flags: USED
 Item  57 -- Length:  109  Offset: 2616 (0x0a38)  Flags: USED
 Item  58 -- Length:  120  Offset: 2496 (0x09c0)  Flags: USED
 Item  59 -- Length:  120  Offset: 2376 (0x0948)  Flags: USED
 Item  60 -- Length:  117  Offset: 2256 (0x08d0)  Flags: USED
 Item  61 -- Length:   94  Offset: 2160 (0x0870)  Flags: USED
 Item  62 -- Length:   95  Offset: 2064 (0x0810)  Flags: USED
 Item  63 -- Length:   72  Offset: 1992 (0x07c8)  Flags: USED
 Item  64 -- Length:   95  Offset: 1896 (0x0768)  Flags: USED
 Item  65 -- Length:  120  Offset: 1776 (0x06f0)  Flags: USED
 Item  66 -- Length:  102  Offset: 1672 (0x0688)  Flags: USED
 Item  67 -- Length:  101  Offset: 1568 (0x0620)  Flags: USED
 Item  68 -- Length:   94  Offset: 1472 (0x05c0)  Flags: USED
 Item  69 -- Length:  120  Offset: 1352 (0x0548)  Flags: USED
 Item  70 -- Length:   95  Offset: 1256 (0x04e8)  Flags: USED
 Item  71 -- Length:  120  Offset: 1136 (0x0470)  Flags: USED
 Item  72 -- Length:  120  Offset: 1016 (0x03f8)  Flags: USED
 Item  73 -- Length:  120  Offset:  896 (0x0380)  Flags: USED
 Item  74 -- Length:  110  Offset:  784 (0x0310)  Flags: USED
 Item  75 -- Length:   94  Offset:  688 (0x02b0)  Flags: USED
 Item  76 -- Length:  102  Offset:  584 (0x0248)  Flags: USED
 Item  77 -- Length:   72  Offset:  512 (0x0200)  Flags: USED
 Item  78 -- Length:   72  Offset:  440 (0x01b8)  Flags: USED
 Item  79 -- Length:  101  Offset:  336 (0x0150)  Flags: USED


*** End of Requested Range Encountered. Last Block Read: 57880 ***