Home Man
Search
Today's Posts
Register

Linux & Unix Commands - Search Man Pages

Plan 9 - man page for join (plan9 section 1)

JOIN(1) 			     General Commands Manual				  JOIN(1)

NAME
       join - relational database operator

SYNOPSIS
       join [ options ] file1 file2

DESCRIPTION
       Join  forms, on the standard output, a join of the two relations specified by the lines of
       file1 and file2.  If one of the file names is the standard input is used.

       File1 and file2 must be sorted in increasing ASCII collating sequence  on  the  fields  on
       which they are to be joined, normally the first in each line.

       There  is one line in the output for each pair of lines in file1 and file2 that have iden-
       tical join fields.  The output line normally consists of the common field, then	the  rest
       of the line from file1, then the rest of the line from file2.

       Input fields are normally separated spaces or tabs; output fields by space.  In this case,
       multiple separators count as one, and leading separators are discarded.

       The following options are recognized, with POSIX syntax.

       -a n   In addition to the normal output, produce a line for each unpairable line  in  file
	      n, where n is 1 or 2.

       -v n   Like -a, omitting output for paired lines.

       -e s   Replace empty output fields by string s.

       -1 m
       -2 m   Join on the mth field of file1 or file2.

       -jn m  Archaic equivalent for -n m.

       -ofields
	      Each output line comprises the designated fields.  The comma-separated field desig-
	      nators are either 0, meaning the join field, or have the form n.m,  where  n  is	a
	      file  number  and m is a field number.  Archaic usage allows separate arguments for
	      field designators.

       -tc    Use character c as the only separator (tab character) on input and  output.   Every
	      appearance of c in a line is significant.

EXAMPLES
       sort /adm/users | join -t: -a 1 -e "" - bdays
	      Add birthdays to password information, leaving unknown birthdays empty.  The layout
	      of is given in users(6); bdays contains sorted lines like

       tr : ' ' </adm/users | sort -k 3 3 >temp
       join -1 3 -2 3 -o 1.1,2.1 temp temp | awk '$1 < $2'
	      Print all pairs of users with identical userids.

SOURCE
       /sys/src/cmd/join.c

SEE ALSO
       sort(1), comm(1), awk(1)

BUGS
       With default field separation, the collating sequence is that of sort -b -ky,y;	with  -t,
       the sequence is that of sort -tx -ky,y.
       One of the files must be randomly accessible.

											  JOIN(1)


All times are GMT -4. The time now is 01:28 AM.

Unix & Linux Forums Content Copyrightę1993-2018. All Rights Reserved.
UNIX.COM Login
Username:
Password:  
Show Password