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OID2NAME(1) PostgreSQL 15.4 Documentation OID2NAME(1)
NAME
oid2name - resolve OIDs and file nodes in a PostgreSQL data directory
SYNOPSIS
oid2name [option...]
DESCRIPTION
oid2name is a utility program that helps administrators to examine the
file structure used by PostgreSQL. To make use of it, you need to be
familiar with the database file structure, which is described in
Chapter 73.
Note
The name "oid2name" is historical, and is actually rather
misleading, since most of the time when you use it, you will really
be concerned with tables' filenode numbers (which are the file
names visible in the database directories). Be sure you understand
the difference between table OIDs and table filenodes!
oid2name connects to a target database and extracts OID, filenode,
and/or table name information. You can also have it show database OIDs
or tablespace OIDs.
OPTIONS
oid2name accepts the following command-line arguments:
-f filenode
--filenode=filenode
show info for table with filenode filenode.
-i
--indexes
include indexes and sequences in the listing.
-o oid
--oid=oid
show info for table with OID oid.
-q
--quiet
omit headers (useful for scripting).
-s
--tablespaces
show tablespace OIDs.
-S
--system-objects
include system objects (those in information_schema, pg_toast and
pg_catalog schemas).
-t tablename_pattern
--table=tablename_pattern
show info for table(s) matching tablename_pattern.
-V
-?
--help
Show help about oid2name command line arguments, and exit.
oid2name also accepts the following command-line arguments for
connection parameters:
-d database
--dbname=database
database to connect to.
-h host
--host=host
database server's host.
-H host
database server's host. Use of this parameter is deprecated as of
PostgreSQL 12.
-p port
--port=port
database server's port.
-U username
--username=username
user name to connect as.
To display specific tables, select which tables to show by using -o, -f
and/or -t. -o takes an OID, -f takes a filenode, and -t takes a table
name (actually, it's a LIKE pattern, so you can use things like foo%).
You can use as many of these options as you like, and the listing will
include all objects matched by any of the options. But note that these
options can only show objects in the database given by -d.
If you don't give any of -o, -f or -t, but do give -d, it will list all
tables in the database named by -d. In this mode, the -S and -i options
control what gets listed.
If you don't give -d either, it will show a listing of database OIDs.
Alternatively you can give -s to get a tablespace listing.
ENVIRONMENT
PGHOST
PGPORT
PGUSER
Default connection parameters.
This utility, like most other PostgreSQL utilities, also uses the
environment variables supported by libpq (see Section 34.15).
The environment variable PG_COLOR specifies whether to use color in
diagnostic messages. Possible values are always, auto and never.
NOTES
oid2name requires a running database server with non-corrupt system
catalogs. It is therefore of only limited use for recovering from
catastrophic database corruption situations.
17255 regression pg_default
17227 template0 pg_default
1 template1 pg_default
$ oid2name -s
All tablespaces:
Oid Tablespace Name
-------------------------
1663 pg_default
1664 pg_global
155151 fastdisk
155152 bigdisk
$ # OK, let's look into database alvherre
$ cd $PGDATA/base/17228
$ # get top 10 db objects in the default tablespace, ordered by size
$ ls -lS * | head -10
-rw------- 1 alvherre alvherre 136536064 sep 14 09:51 155173
-rw------- 1 alvherre alvherre 17965056 sep 14 09:51 1155291
-rw------- 1 alvherre alvherre 1204224 sep 14 09:51 16717
-rw------- 1 alvherre alvherre 581632 sep 6 17:51 1255
-rw------- 1 alvherre alvherre 237568 sep 14 09:50 16674
-rw------- 1 alvherre alvherre 212992 sep 14 09:51 1249
-rw------- 1 alvherre alvherre 204800 sep 14 09:51 16684
-rw------- 1 alvherre alvherre 196608 sep 14 09:50 16700
-rw------- 1 alvherre alvherre 163840 sep 14 09:50 16699
-rw------- 1 alvherre alvherre 122880 sep 6 17:51 16751
$ # I wonder what file 155173 is ...
$ oid2name -d alvherre -f 155173
From database "alvherre":
Filenode Table Name
----------------------
155173 accounts
$ # you can ask for more than one object
$ oid2name -d alvherre -f 155173 -f 1155291
From database "alvherre":
Filenode Table Name
-------------------------
155173 accounts
1155291 accounts_pkey
$ # you can mix the options, and get more details with -x
$ oid2name -d alvherre -t accounts -f 1155291 -x
From database "alvherre":
Filenode Table Name Oid Schema Tablespace
------------------------------------------------------
155173 accounts 155173 public pg_default
1155291 accounts_pkey 1155291 public pg_default
$ # show disk space for every db object
$ du [0-9]* |
> while read SIZE FILENODE
> do
> echo "$SIZE `oid2name -q -d alvherre -i -f $FILENODE`"
> done
16 1155287 branches_pkey
> echo "$SIZE `oid2name -q -d alvherre -f $FN`"
> done
133466 155173 accounts
17561 1155291 accounts_pkey
1177 16717 pg_proc_proname_args_nsp_index
...
$ # If you want to see what's in tablespaces, use the pg_tblspc directory
$ cd $PGDATA/pg_tblspc
$ oid2name -s
All tablespaces:
Oid Tablespace Name
-------------------------
1663 pg_default
1664 pg_global
155151 fastdisk
155152 bigdisk
$ # what databases have objects in tablespace "fastdisk"?
$ ls -d 155151/*
155151/17228/ 155151/PG_VERSION
$ # Oh, what was database 17228 again?
$ oid2name
All databases:
Oid Database Name Tablespace
----------------------------------
17228 alvherre pg_default
17255 regression pg_default
17227 template0 pg_default
1 template1 pg_default
$ # Let's see what objects does this database have in the tablespace.
$ cd 155151/17228
$ ls -l
total 0
-rw------- 1 postgres postgres 0 sep 13 23:20 155156
$ # OK, this is a pretty small table ... but which one is it?
$ oid2name -d alvherre -f 155156
From database "alvherre":
Filenode Table Name
----------------------
155156 foo
AUTHOR
B. Palmer <bpalmer@crimelabs.net>
PostgreSQL 15.4 2023 OID2NAME(1)