oid2name — resolve OIDs and file nodes in a PostgreSQL data directory
vacuumlo — remove orphaned large objects from a PostgreSQL database
This section covers PostgreSQL client applications in contrib. They can be run from anywhere, independent of where the database server resides. See also PostgreSQL Client Applications for information about client applications that part of the core PostgreSQL distribution.
oid2name — resolve OIDs and file nodes in a PostgreSQL data directory
oid2name [option...]
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 66.
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.
oid2name accepts the following command-line arguments:-f filenode
show info for table with filenode filenode-i
include indexes and sequences in the listing-o oid
show info for table with OID oid-q
omit headers (useful for scripting)-s
show tablespace OIDs-S
include system objects (those in information_schema, pg_toast and pg_catalog schemas)-t tablename_pattern
show info for table(s) matching tablename_pattern-V
--version
Print the oid2name version and exit.-x
display more information about each object shown: tablespace name, schema name, and OID-?
--help
Show help about oid2name command line arguments, and exit.
oid2name also accepts the following command-line arguments for connection parameters:-d database
database to connect to-H host
database server's host-p port
database server's port-U username
user name to connect as-P password
password (deprecated — putting this on the command line is a security hazard)
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.
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.
B. Palmer <bpalmer@crimelabs.net>
vacuumlo — remove orphaned large objects from a PostgreSQL database
vacuumlo [option...] dbname...
vacuumlo is a simple utility program that will remove any “orphaned” large objects from a PostgreSQL database. An orphaned large object (LO) is considered to be any LO whose OID does not appear in any oid or lo data column of the database.
If you use this, you may also be interested in the lo_manage trigger in the module. lo_manage is useful to try to avoid creating orphaned LOs in the first place.
All databases named on the command line are processed.
vacuumlo accepts the following command-line arguments:-l limit
Remove no more than limit large objects per transaction (default 1000). Since the server acquires a lock per LO removed, removing too many LOs in one transaction risks exceeding . Set the limit to zero if you want all removals done in a single transaction.-n
Don't remove anything, just show what would be done.-v
Write a lot of progress messages.-V
--version
Print the vacuumlo version and exit.-?
--help
Show help about vacuumlo command line arguments, and exit.
vacuumlo also accepts the following command-line arguments for connection parameters:-h hostname
Database server's host.-p port
Database server's port.-U username
User name to connect as.-w
--no-password
Never issue a password prompt. If the server requires password authentication and a password is not available by other means such as a .pgpass file, the connection attempt will fail. This option can be useful in batch jobs and scripts where no user is present to enter a password.-W
Force vacuumlo to prompt for a password before connecting to a database.
This option is never essential, since vacuumlo will automatically prompt for a password if the server demands password authentication. However, vacuumlo will waste a connection attempt finding out that the server wants a password. In some cases it is worth typing -W to avoid the extra connection attempt.
vacuumlo works by the following method: First, vacuumlo builds a temporary table which contains all of the OIDs of the large objects in the selected database. It then scans through all columns in the database that are of type oid or lo, and removes matching entries from the temporary table. (Note: Only types with these names are considered; in particular, domains over them are not considered.) The remaining entries in the temporary table identify orphaned LOs. These are removed.
Peter Mount <>