1DBSORT(1)             User Contributed Perl Documentation            DBSORT(1)
2
3
4

NAME

6       dbsort - sort rows based on the the specified columns
7

SYNOPSIS

9           dbsort [-M MemLimit] [-T TemporaryDirectory] [-nNrR] column [column...]
10

DESCRIPTION

12       Sort all input rows as specified by the numeric or lexical columns.
13
14       Dbsort consumes a fixed amount of memory regardless of input size.  (It
15       reverts to temporary files on disk if necessary, based on the -M and -T
16       options.)
17
18       The sort should be stable, but this has not yet been verified.
19
20       For large inputs (those that spill to disk), dbsort will do some of the
21       merging in parallel, if possible.  The --parallel option can control
22       the degree of parallelism, if desired.
23

OPTIONS

25       General option:
26
27       -M MaxMemBytes
28           Specify an approximate limit on memory usage (in bytes).  Larger
29           values allow faster sorting because more operations happen in-
30           memory, provided you have enough memory.
31
32       -T TmpDir
33           where to put tmp files.  Also uses environment variable TMPDIR, if
34           -T is not specified.  Default is /tmp.
35
36       --parallelism N or -j N
37           Allow up to N merges to happen in parallel.  Default is the number
38           of CPUs in the machine.
39
40       Sort specification options (can be interspersed with column names):
41
42       -r or --descending
43           sort in reverse order (high to low)
44
45       -R or --ascending
46           sort in normal order (low to high)
47
48       -t or --type-inferred-sorting
49           sort fields by type (numeric or leicographic), automatically
50
51       -T or --no-type-inferred-sorting
52           sort fields only as specified based on "-n" or "-N"
53
54       -n or --numeric
55           sort numerically
56
57       -N or --lexical
58           sort lexicographically
59
60       This module also supports the standard fsdb options:
61
62       -d  Enable debugging output.
63
64       -i or --input InputSource
65           Read from InputSource, typically a file name, or "-" for standard
66           input, or (if in Perl) a IO::Handle, Fsdb::IO or Fsdb::BoundedQueue
67           objects.
68
69       -o or --output OutputDestination
70           Write to OutputDestination, typically a file name, or "-" for
71           standard output, or (if in Perl) a IO::Handle, Fsdb::IO or
72           Fsdb::BoundedQueue objects.
73
74       --autorun or --noautorun
75           By default, programs process automatically, but Fsdb::Filter
76           objects in Perl do not run until you invoke the run() method.  The
77           "--(no)autorun" option controls that behavior within Perl.
78
79       --header H
80           Use H as the full Fsdb header, rather than reading a header from
81           then input.
82
83       --help
84           Show help.
85
86       --man
87           Show full manual.
88

SAMPLE USAGE

90   Input:
91           #fsdb cid cname
92           10 pascal
93           11 numanal
94           12 os
95
96   Command:
97           cat data.fsdb | dbsort cname
98
99   Output:
100           #fsdb      cid     cname
101           11 numanal
102           12 os
103           10 pascal
104           #  | dbsort cname
105

SEE ALSO

107       dbmerge(1), dbmapreduce(1), Fsdb(3)
108

110       Copyright (C) 1991-2018 by John Heidemann <johnh@isi.edu>
111
112       This program is distributed under terms of the GNU general public
113       license, version 2.  See the file COPYING with the distribution for
114       details.
115
116
117
118perl v5.38.0                      2023-07-20                         DBSORT(1)
Impressum