1. Computing
Linux / Unix Command: join
Command Library

NAME

join - join lines of two files on a common field  

SYNOPSIS

join [OPTION]... FILE1 FILE2  

DESCRIPTION

For each pair of input lines with identical join fields, write a line to standard output. The default join field is the first, delimited by whitespace. When FILE1 or FILE2 (not both) is -, read standard input.

-a SIDE
print unpairable lines coming from file SIDE
-e EMPTY
replace missing input fields with EMPTY
-i, --ignore-case ignore differences in case when comparing fields
-j FIELD
(obsolescent) equivalent to `-1 FIELD -2 FIELD'
-j1 FIELD
(obsolescent) equivalent to `-1 FIELD'
-j2 FIELD
(obsolescent) equivalent to `-2 FIELD'
-o FORMAT
obey FORMAT while constructing output line
-t CHAR
use CHAR as input and output field separator
-v SIDE
like -a SIDE, but suppress joined output lines
-1 FIELD
join on this FIELD of file 1
-2 FIELD
join on this FIELD of file 2
--help
display this help and exit
--version
output version information and exit

Unless -t CHAR is given, leading blanks separate fields and are ignored, else fields are separated by CHAR. Any FIELD is a field number counted from 1. FORMAT is one or more comma or blank separated specifications, each being `SIDE.FIELD' or `0'. Default FORMAT outputs the join field, the remaining fields from FILE1, the remaining fields from FILE2, all separated by CHAR.  

SEE ALSO

The full documentation for join is maintained as a Texinfo manual. If the info and join programs are properly installed at your site, the command
info join

should give you access to the complete manual.


Important: Use the man command (% man) to see how a command is used on your particular computer.

>> Linux/Unix Command Library

>> Shell Command Library

Discuss in my forum

©2014 About.com. All rights reserved.