initdb
initdb — create a new Postgres Pro database cluster
Synopsis
initdb
[option
...] [ --pgdata
| -D
] directory
Description
initdb
creates a new Postgres Pro database cluster. A database cluster is a collection of databases that are managed by a single server instance.
Creating a database cluster consists of creating the directories in which the database data will live, generating the shared catalog tables (tables that belong to the whole cluster rather than to any particular database), and creating the template1
and postgres
databases. When you later create a new database, everything in the template1
database is copied. (Therefore, anything installed in template1
is automatically copied into each database created later.) The postgres
database is a default database meant for use by users, utilities and third party applications.
Although initdb
will attempt to create the specified data directory, it might not have permission if the parent directory of the desired data directory is root-owned. To initialize in such a setup, create an empty data directory as root, then use chown
to assign ownership of that directory to the database user account, then su
to become the database user to run initdb
.
initdb
must be run as the user that will own the server process, because the server needs to have access to the files and directories that initdb
creates. Since the server cannot be run as root, you must not run initdb
as root either. (It will in fact refuse to do so.)
initdb
initializes the database cluster's default locale and character set encoding. The character set encoding, collation order (LC_COLLATE
) and character set classes (LC_CTYPE
, e.g., upper, lower, digit) can be set separately for a database when it is created. initdb
determines those settings for the template1
database, which will serve as the default for all other databases.
To alter the default collation order or character set classes, use the --lc-collate
and --lc-ctype
options. Collation orders other than C
or POSIX
also have a performance penalty. For these reasons it is important to choose the right locale when running initdb
.
The remaining locale categories can be changed later when the server is started. You can also use --locale
to set the default for all locale categories, including collation order and character set classes. All server locale values (lc_*
) can be displayed via SHOW ALL
. More details can be found in Section 22.1.
To alter the default encoding, use the --encoding
. More details can be found in Section 22.3.
Options
-A
authmethod
--auth=
authmethod
This option specifies the default authentication method for local users used in
pg_hba.conf
(host
andlocal
lines).initdb
will prepopulatepg_hba.conf
entries using the specified authentication method for non-replication as well as replication connections.Do not use
trust
unless you trust all local users on your system.trust
is the default for ease of installation.--auth-host=
authmethod
This option specifies the authentication method for local users via TCP/IP connections used in
pg_hba.conf
(host
lines).--auth-local=
authmethod
This option specifies the authentication method for local users via Unix-domain socket connections used in
pg_hba.conf
(local
lines).-D
directory
--pgdata=
directory
This option specifies the directory where the database cluster should be stored. This is the only information required by
initdb
, but you can avoid writing it by setting thePGDATA
environment variable, which can be convenient since the database server (postgres
) can find the database directory later by the same variable.-E
encoding
--encoding=
encoding
Selects the encoding of the template database. This will also be the default encoding of any database you create later, unless you override it there. The default is derived from the locale, or
SQL_ASCII
if that does not work. The character sets supported by the Postgres Pro server are described in Section 22.3.1.-k
--data-checksums
Use checksums on data pages to help detect corruption by the I/O system that would otherwise be silent. Enabling checksums may incur a noticeable performance penalty. This option can only be set during initialization, and cannot be changed later. If set, checksums are calculated for all objects, in all databases.
By default, Postgres Pro clusters are initialized with checksums enabled. To change this behavior, provide the
--no-data-checksums
option.--no-data-checksums
Disable checksums on data pages.
By default, Postgres Pro clusters are initialized with checksums enabled.
--locale=
locale
[@provider
]Sets the default locale for the database cluster. If this option is not specified, the locale is inherited from the environment that
initdb
runs in. Locale support is described in Section 22.1.Optionally, you can specify the provider of the default collation after the
@
symbol. Supported values areicu
andlibc
. For details, see Section 22.2.2.--lc-collate=
locale
[@provider
]--lc-ctype=
locale
--lc-messages=
locale
--lc-monetary=
locale
--lc-numeric=
locale
--lc-time=
locale
Like
--locale
, but only sets the locale in the specified category.--no-locale
Equivalent to
--locale=C
.-N
--no-sync
By default,
initdb
will wait for all files to be written safely to disk. This option causesinitdb
to return without waiting, which is faster, but means that a subsequent operating system crash can leave the data directory corrupt. Generally, this option is useful for testing, but should not be used when creating a production installation.--pwfile=
filename
Makes
initdb
read the database superuser's password from a file. The first line of the file is taken as the password.-S
--sync-only
Safely write all database files to disk and exit. This does not perform any of the normal initdb operations.
-T
config
--text-search-config=
config
Sets the default text search configuration. See default_text_search_config for further information.
-U
username
--username=
username
Selects the user name of the database superuser. This defaults to the name of the effective user running
initdb
. It is really not important what the superuser's name is, but one might choose to keep the customary name postgres, even if the operating system user's name is different.-W
--pwprompt
Makes
initdb
prompt for a password to give the database superuser. If you don't plan on using password authentication, this is not important. Otherwise you won't be able to use password authentication until you have a password set up.-X
directory
--waldir=
directory
This option specifies the directory where the write-ahead log should be stored.
Other, less commonly used, options are also available:
-d
--debug
Print debugging output from the bootstrap backend and a few other messages of lesser interest for the general public. The bootstrap backend is the program
initdb
uses to create the catalog tables. This option generates a tremendous amount of extremely boring output.-L
directory
Specifies where
initdb
should find its input files to initialize the database cluster. This is normally not necessary. You will be told if you need to specify their location explicitly.-n
--no-clean
By default, when
initdb
determines that an error prevented it from completely creating the database cluster, it removes any files it might have created before discovering that it cannot finish the job. This option inhibits tidying-up and is thus useful for debugging.
Other options:
-V
--version
Print the initdb version and exit.
-?
--help
Show help about initdb command line arguments, and exit.
Environment
PGDATA
Specifies the directory where the database cluster is to be stored; can be overridden using the
-D
option.TZ
Specifies the default time zone of the created database cluster. The value should be a full time zone name (see Section 8.5.3).
This utility, like most other Postgres Pro utilities, also uses the environment variables supported by libpq (see Section 31.14).
Notes
initdb
can also be invoked via pg_ctl initdb
.