DBSORT(1)

NAME
dbsort - sort rows based on the the specified columns

SYNOPSIS
    dbsort [-M MemLimit] [-T TemporaryDirectory] [-nNrR] column [column...]

DESCRIPTION
Sort all input rows as specified by the numeric or lexical columns.

Dbsort consumes a fixed amount of memory regardless of input size. (It reverts to temporary files on disk if necessary, based on the -M and -T options.)

The sort should be stable, but this has not yet been verified.

OPTIONS
General option:

-M MaxMemBytes
    Specify an approximate limit on memory usage (in bytes). Larger values allow faster sorting because more operations happen in-memory, provided you have enough memory.

-T TmpDir
    where to put tmp files. Also uses environment variable TMPDIR, if -T is not specified. Default is /tmp.

Sort specification options (can be interspersed with column names):

-r or --descending
    sort in reverse order (high to low)

-R or --ascending
    sort in normal order (low to high)

-n or --numeric
    sort numerically

-N or --lexical
    sort lexicographically

This module also supports the standard fsdb options:

-d  Enable debugging output.

-i or --input InputSource
    Read from InputSource, typically a file name, or "-" for standard input, or (if in Perl) a IO::Handle, Fsdb::IO or Fsdb::BoundedQueue objects.

-o or --output OutputDestination
    Write to OutputDestination, typically a file name, or "-" for standard output, or (if in Perl) a IO::Handle, Fsdb::IO or Fsdb::BoundedQueue objects.

--autorun or --noautorun
    By default, programs process automatically, but Fsdb::Filter objects in Perl do not run until you invoke the run() method. The "--(no)autorun" option controls that behavior within Perl.

--help
    Show help.

--man
    Show full manual.

SAMPLE USAGE

  Input:
    #fsdb cid cname
    10 pascal
    11 numanal
    12 os

  Command:
    cat data.fsdb | dbsort cname

  Output:
    #fsdb      cid     cname
    11 numanal
    12 os
    10 pascal
    #  | dbsort cname

SEE ALSO
dbmerge(1), dbmapreduce(1), Fsdb(3)

AUTHOR and COPYRIGHT
Copyright (C) 1991-2008 by John Heidemann <johnh@isi.edu>

This program is distributed under terms of the GNU general public license, version 2. See the file COPYING with the distribution for details.