Copyright (c) 2002-2010 Red Hat, Inc.
Copyright (c) 2011-2023, PostgreSQL Global Development Group
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
Original Author: Patrick Macdonald patrickm@redhat.com
pg_filedump is a utility to format PostgreSQL heap/index/control files into a human-readable form. You can format/dump the files several ways, as listed in the Invocation section, as well as dumping straight binary.
The type of file (heap/index) can usually be determined automatically by the content of the blocks within the file. However, to format a pg_control file you must use the -c option.
The default is to format the entire file using the block size listed in block 0 and display block relative addresses. These defaults can be modified using run-time options.
Some options may seem strange but they're there for a reason. For example, block size. It's there because if the header of block 0 is corrupt, you need a method of forcing a block size.
To compile pg_filedump, you will need to have a properly configured PostgreSQL source tree or the devel packages (with include files) of the appropriate PostgreSQL major version.
make PG_CONFIG=/path/to/postgresql/bin/pg_config
make install PG_CONFIG=/path/to/postgresql/bin/pg_config
Usage: pg_filedump [-abcdfhikxy] [-R startblock [endblock]] [-D attrlist] [-S blocksize] [-s segsize] [-n segnumber] file
Display formatted contents of a PostgreSQL heap/index/control file
Defaults are: relative addressing, range of the entire file, block
size as listed on block 0 in the file
The following options are valid for heap and index files:
-a Display absolute addresses when formatting (Block header
information is always block relative)
-b Display binary block images within a range (Option will turn
off all formatting options)
-d Display formatted block content dump (Option will turn off
all other formatting options)
-D Decode tuples using given comma separated list of types
Supported types:
bigint bigserial bool char charN date float float4 float8 int
json macaddr name numeric oid real serial smallint smallserial text
time timestamp timestamptz timetz uuid varchar varcharN xid xml
~ ignores all attributes left in a tuple
-f Display formatted block content dump along with interpretation
-h Display this information
-i Display interpreted item details
-k Verify block checksums
-o Do not dump old values.
-R Display specific block ranges within the file (Blocks are
indexed from 0)
[startblock]: block to start at
[endblock]: block to end at
A startblock without an endblock will format the single block
-s Force segment size to [segsize]
-t Dump TOAST files
-v Ouput additional information about TOAST relations
-n Force segment number to [segnumber]
-S Force block size to [blocksize]
-x Force interpreted formatting of block items as index items
-y Force interpreted formatting of block items as heap items
The following options are valid for control files:
-c Interpret the file listed as a control file
-f Display formatted content dump along with interpretation
-S Force block size to [blocksize]
Additional functions:
-m Interpret file as pg_filenode.map file and print contents (all
other options will be ignored)
Report bugs to <pgsql-bugs@postgresql.org>
In most cases it's recommended to use the -i and -f options to get the most useful dump output.