Fsdb::Filter::dbcolsplittorows

NAME

dbcolsplittorows - split an existing column into multiple new rows

SYNOPSIS

dbcolsplittorows [-C ElementSeperator] [-e null] [-E] [-N enumerated-name] column [column...]

DESCRIPTION

Split column into pieces, outputting one row for each piece.

By default, any empty fields are ignored. If an empty field value is given with -e, then they produce output.

When a null value is given, empty fields at the beginning and end of lines are suppressed (like perl split). Unlike perl, if ALL fields are empty, we generate one (and not zero) empty fields.

The inverse of this commend is dbfilepivot.

OPTIONS

-C S or --element-separator S

Specify the separator used to split columns. (Defaults to a single underscore.)

-E or --enumerate

Enumerate output columns: rather than assuming the column name uses the element separator, we keep it whole and fill in with indexes starting from 0.

-N or --new-name N

Name the new column N for enumeration. Defaults to "index".

-e E or --empty E

give value E as the value for empty (null) records

This module also supports the standard fsdb options:

-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 name uid
John_Heidemann 2274
Greg_Johnson 2275
Root 0
# this is a simple database
# | dbcol fullname uid
# | dbcolrename fullname name

Command:
cat data.fsdb | dbcolsplittorows name

Output:
#fsdb name uid
John 2274
Heidemann 2274
Greg 2275
Johnson 2275
Root 0
# this is a simple database
# | dbcol fullname uid
# | dbcolrename fullname name
# | dbcolsplittorows name

SEE ALSO

Fsdb(1). dbcolmerge(1). dbcolsplittocols(1). dbcolrename(1). dbfilepvot(1).

CLASS FUNCTIONS

new
$filter = new Fsdb::Filter::dbcolsplittocols(@arguments);

Create a new dbcolsplittocols object, taking command-line arguments.

set_defaults
$filter->set_defaults();

Internal: set up defaults.

parse_options
$filter->parse_options(@ARGV);

Internal: parse command-line arguments.

setup
$filter->setup();

Internal: setup, parse headers.

run
$filter->run();

Internal: run over each rows.

AUTHOR and COPYRIGHT

Copyright (C) 1991-2018 by John Heidemann <johnh AT isi DOT edu>

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