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NAME

       db4.8_load - Load data from standard input

SYNOPSIS

       db4.8_load [-nTV] [-c name=value] [-f file] [-h home] [-P password] [-t
       btree | hash | queue | recno] file

       db4.8_load [-r lsn | fileid] [-h home] [-P password] file

DESCRIPTION

       The db4.8_load utility reads from the standard input and loads it  into
       the  database file. The database file is created if it does not already
       exist.

       The input to db4.8_load must be in the output format specified  by  the
       db4.8_dump utility, utilities, or as specified for the -T below.

OPTIONS

       -c     Specify  configuration  options ignoring any value they may have
              based on the input.  The command-line format is name=value.  See
              the  Supported  Keywords  section  below  for a list of keywords
              supported by the -c option.

       -f     Read from the specified input file instead of from the  standard
              input.

       -h     Specify a home directory for the database environment.

              If  a  home  directory is specified, the database environment is
              opened  using  the  DB_INIT_LOCK,  DB_INIT_LOG,   DB_INIT_MPOOL,
              DB_INIT_TXN,  and  DB_USE_ENVIRON  flags to DB_ENV->open.  (This
              means that db4.8_load can be used to load  data  into  databases
              while  they  are in use by other processes.) If the DB_ENV->open
              call fails, or if no home directory is specified,  the  database
              is  still  updated, but the environment is ignored; for example,
              no locking is done.

       -n     Do not overwrite existing keys in the database when loading into
              an  already  existing  database.   If  a key/data pair cannot be
              loaded into the database for this reason, a warning  message  is
              displayed  on  the  standard error output, and the key/data pair
              are skipped.

       -P     Specify an environment password.  Although Berkeley DB utilities
              overwrite  password  strings as soon as possible, be aware there
              may be a window of vulnerability on systems  where  unprivileged
              users  can see command-line arguments or where utilities are not
              able  to  overwrite  the  memory  containing  the   command-line
              arguments.

       -r     Reset the database’s file ID or log sequence numbers (LSNs).

              All   database   pages  in  transactional  environments  contain
              references to the environment’s log records.  In order to copy a
              database  into  a  different database environment, database page
              references to the old environment’s log records must  be  reset,
              otherwise  data  corruption  can  occur  when  the  database  is
              modified in the new environment.  The -r  lsn  option  resets  a
              database’s log sequence numbers.

              All databases contain an ID string used to identify the database
              in the database environment cache.  If a database is copied, and
              used  in  the  same environment as another file with the same ID
              string, corruption can occur.  The -r fileid   option  resets  a
              database’s file ID to a new value.

              In  both cases, the physical file specified by the file argument
              is modified in-place.

       -T     The -T option allows non-Berkeley DB applications to easily load
              text files into databases.

              If  the  database to be created is of type Btree or Hash, or the
              keyword keys is specified as set, the input must be paired lines
              of  text,  where the first line of the pair is the key item, and
              the second line of the pair is its corresponding data item.   If
              the  database  to  be  created is of type Queue or Recno and the
              keyword keys is not set, the input must be lines of text,  where
              each line is a new data item for the database.

              A  simple  escape  mechanism,  where  newline  and backslash (\)
              characters are special, is applied to the text  input.   Newline
              characters  are  interpreted  as  record  separators.  Backslash
              characters in the text will be interpreted in one of  two  ways:
              If the backslash character precedes another backslash character,
              the pair will be interpreted as a  literal  backslash.   If  the
              backslash  character  precedes  any  other  character,  the  two
              characters following the backslash  will  be  interpreted  as  a
              hexadecimal  specification  of  a single character; for example,
              \0a is a newline character in the ASCII character set.

              For this  reason,  any  backslash  or  newline  characters  that
              naturally  occur  in  the  text  input  must be escaped to avoid
              misinterpretation by db4.8_load.

              If the -T option is specified, the underlying access method type
              must be specified using the -t option.

       -t     Specify  the  underlying  access  method.   If  no  -t option is
              specified, the database will be loaded into a  database  of  the
              same  type  as  was dumped; for example, a Hash database will be
              created if a Hash database was dumped.

              Btree and Hash databases may be converted from one to the other.
              Queue  and  Recno  databases  may  be  converted from one to the
              other.  If the -k option was specified on the call to db4.8_dump
              then  Queue  and  Recno  databases  may be converted to Btree or
              Hash, with the key being the integer record number.

       -V     Write the library version number to  the  standard  output,  and
              exit.

       The  db4.8_load  utility may be used with a Berkeley DB environment (as
       described for the -h  option,  the  environment  variable  DB_HOME,  or
       because  the  utility  was  run in a directory containing a Berkeley DB
       environment).  In order to avoid environment corruption  when  using  a
       Berkeley  DB  environment, db4.8_load should always be given the chance
       to  detach  from  the  environment  and  exit  gracefully.   To   cause
       db4.8_load  to release all environment resources and exit cleanly, send
       it an interrupt signal (SIGINT).

       The db4.8_load utility exits 0 on success, 1 if one  or  more  key/data
       pairs  were  not  loaded  into  the  database  because  the key already
       existed, and >1 if an error occurs.

EXAMPLES

       The db4.8_load utility can be used to load text files  into  databases.
       For  example, the following command loads the standard UNIX /etc/passwd
       file into a database, with the login name  as  the  key  item  and  the
       entire password entry as the data item:

       awk  -F:  ’{print  $1;  print  $0}’ < /etc/passwd | sed ’s/\\/\\\\/g’ |
       db4.8_load -T -t hash passwd.db

       Note that backslash characters naturally  occurring  in  the  text  are
       escaped to avoid interpretation as escape characters by db4.8_load.

ENVIRONMENT

       DB_HOME
              If  the  -h option is not specified and the environment variable
              DB_HOME is set, it is used as the path of the database home,  as
              described in DB_ENV->open.

SUPPORTED KEYWORDS

       The  following  keywords are supported for the -c command-line ption to
       the db4.8_load utility.  See DB->open for further discussion  of  these
       keywords and what values should be specified.

       The   parenthetical  listing  specifies  how  the  value  part  of  the
       name=value pair is interpreted.  Items listed as (boolean) expect value
       to  be 1 (set) or 0 (unset).  Items listed as (number) convert value to
       a number.  Items listed  as  (string)  use  the  string  value  without
       modification.

       bt_minkey
              The minimum number of keys per page.

       chksum Enable page checksums.

       database
              The database to load.

       db_lorder
              The byte order for integers in the stored database metadata.

       db_pagesize
              The size of database pages, in bytes.

       duplicates
              The value of the DB_DUP flag.

       dupsort
              The value of the DB_DUPSORT flag.

       extentsize
              The  size  of  database  extents,  in pages, for Queue databases
              configured to use extents.

       h_ffactor
              The density within the Hash database.

       h_nelem
              The size of the Hash database.

       keys   Specify whether keys are present for Queue or Recno databases.

       re_len Specify fixed-length records of the specified length.

       re_pad Specify the fixed-length record pad character.

       recnum The value of the DB_RECNUM flag.

       renumber
              The value of the DB_RENUMBER flag.

       subdatabase
              The subdatabase to load.

AUTHORS

       Sleepycat Software, Inc. This manual page was created based on the HTML
       documentation   for   db_load   from   Sleepycat,  by  Thijs  Kinkhorst
       <thijs@kinkhorst.com>, for the  Debian  system  (but  may  be  used  by
       others).

                               22 November 2009