Ubuntu Manpage: join-dctrl - perform relational join on data in dctrl format

NAME

       join-dctrl - perform relational join on data in dctrl format

SYNOPSIS

       join-dctrl [ options ] filename filename

       join-dctrl --version

       join-dctrl --help

DESCRIPTION

       join-dctrl performs a relational join operation on data given to it in Debian control file
       format.

       A join field must be specified using either the switches -1  and  -2  or  the  switch  -j.
       Conceptually,  the  program  creates  all  ordered  pairs of records that can be formed by
       having a record from the first file as the first member of the pair and  having  a  record
       from  the second file as the second member of the pair; and then it deletes all such pairs
       where the join fields are not equal.  Effectively, each of the input files is treated as a
       relational database table.

       Every  input file must be in ascending order on its join field; this allows the program to
       work fast.  The sort-dctrl(1) program can be used to make it so.

OPTIONS

-1 field, --1st-join-field=field
Specify the join field of the first input file.

-2 field, --2nd-join-field=field
Specify the join field of the second input file.

-j field, --join-field=field
Specify a common join field for all files.

-a fileno, --unpairable-from=fileno
Specify that unmatched paragraphs from the first (if 1 is given) or the second (if
2 is given) file are printed.

-o fieldspec, --output-fields=fieldspec
Specify which fields are included in the output. Fields are separated by commas
(more than one -o option can be used, too). Each field is specified in the format
fileno.field in which fileno is the ordinal number of the input file from which the
field is drawn (either 1 or 2), and field gives the name of the field to use. As a
special case, simple 0 can be used instead of fileno.field to refer to the common
value of the join fields.

The name of the field (not including the file number) is used in the output as the
name of the field. However, a different name for output purposes can be specified
by suffixing the field specification by a colon and the preferred visible name.

For example, the option -o 0,1.Version:Old-Version,2.Version specifies that the
first field in any output record should be the join field, the second field should
be Old-Version drawing its data from the Version field of the first input file, and
the third field should be Version drawing its data from the field with the same
name in the second input file, and these are the only fields in an output record.

If no -o option is given, all fields of all the records being joined are included
in the output.

-l level, --errorlevel=level
Set log level to level. level is one of fatal, important, informational and debug,
but the last may not be available, depending on the compile-time options. These
categories are given here in order; every message that is emitted when fatal is in
effect, will be emitted in the important error level, and so on. The default is
important.

-V, --version
Print out version information.

-C, --copying
Print out the copyright license. This produces much output; be sure to redirect or
pipe it somewhere (such as your favourite pager).

-h, --help
Print out a help summary.

OPERANDS

       join-dctrl will treat each file named on the command line as a relational database  table.
       A  file  called  - represents the program's standard input stream.  Currently, exactly two
       files must be named.

STDIN

       The standard input stream may be used as input as specified above in the OPERANDS section.

INPUT FILES

       All input to join-dctrl is in the format of a Debian control file.

       A Debian control (dctrl) file is  a  semistructured  single-table  database  stored  in  a
       machine-parseable text file.  Such a database consists of a set of records; each record is
       a mapping from field names to field content.  Textually, records are  separated  by  empty
       lines, while each field is encoded as one or more nonempty lines inside a record.  A field
       starts with its name, followed by a colon, followed by the field content.  The colon  must
       reside  on  the first line of the field, and the first line must start with no whitespace.
       Subsequent lines, in contrast, always start with linear whitespace (one or more  space  or
       tab characters).

       Each input file must be in the ascending order of its join field.

ENVIRONMENT VARIABLES

       The  standard  locale  environment,  specifically  its  character set setting, affects the
       interpretation of input and output as character streams.

ASYNCHRONOUS EVENTS

       Standard UNIX signals have their usual meaning.

STDOUT

       All output is sent to the standard output stream.  The output is in the format of a Debian
       control  file,  described  above  in  the  INPUT FILES section.  The output will be in the
       ascending order of the join field, if that field is included in the output.

OUTPUT FILES

       There are no output files.

EXIT STATUS

       This utility exits with 0 when successful.  It uses a  nonzero  exit  code  inconsistently
       when an error is noticed (this is a bug).

CONSEQUENCES OF ERRORS

       In  case  of  errors in the input, the output will be partially or completely garbage.  In
       case of errors in invocation, the program will refuse to function.

EXAMPLES

       Suppose that a file containing data about  binary  packages  for  the  AMD64  architecture
       contained  in  the Debian squeeze (6.0) release, section main, is in the current directory
       and named Packages.  Suppose that we are currently on a Debian  system.   Suppose  further
       that  the  current  directory  does  not  contain files named stat and pkg.  The following
       commands gives, for each package currently  installed  and  available  in  Debian  squeeze
       (6.0),  its  currently  installed  version (as Old-Version) and the version in squeeze (as
       New-Version):
       $ sort-dctrl -kPackage /var/lib/dpkg/status > stat
       $ sort-dctrl -kPackage Packages > pkg
       $ join-dctrl -j Package \
         -o 0,1.Version:Old-Version,2.Version:New-Version \
         stat pkg

AUTHOR

       The join-dctrl program and this manual page were written by Antti-Juhani Kaijanaho.