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       initdb - create a new PostgreSQL database cluster


       initdb [ option... ]   [ --pgdata  ]  [ -D  ] directory


       initdb creates a new PostgreSQL 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

       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 in the documentation.

       To alter the default encoding, use the --encoding.  More details can be
       found in in the documentation.


       -A authmethod

              This option specifies the authentication method for local  users
              used in pg_hba.conf. Do not use trust unless you trust all local
              users  on  your  system.  Trust  is  the  default  for  ease  of

       -D 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 the PGDATA
              environment variable, which can be convenient since the database
              server  (postgres)  can find the database directory later by the
              same variable.

       -E 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 PostgreSQL server are described in in the  documentation.

              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 in the






              Like --locale,  but  only  sets  the  locale  in  the  specified

       -X directory

              This  option  specifies  the directory where the transaction log
              should be stored.

       -U 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.


              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.

              Makes initdb read the database superuser’s password from a file.
              The first line of the file is taken as the password.

       Other, less commonly used, parameters are also available:


              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.


              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.


       PGDATA Specifies the directory where the  database  cluster  is  to  be
              stored; can be overridden using the -D option.

       This  utility,  like  most  other  PostgreSQL  utilities, also uses the
       environment variables supported by libpq (see in the documentation).