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join(1)				 User Commands			       join(1)

       join - relational database operator

       join [-a	filenumber | -v	filenumber]  [-1 fieldnumber] [-2 fieldnumber]
       [-o list] [-e string] [-t char] file1 file2

       join [-a	filenumber] [-j	fieldnumber] [-j1 fieldnumber]	[-j2 fieldnum-
       ber] [-o	list] [-e string] [-t char] file1 file2

       The join	command	forms, on the standard output, a join of the two rela-
       tions specified by the lines of file1 and file2.

       There is	one line in the	output for each	pair of	 lines	in  file1  and
       file2  that  have  identical join fields. The output line normally con-
       sists of	the common field, then the rest	of the line from  file1,  then
       the  rest  of  the line from file2. This	format can be changed by using
       the -o option (see below). The -a option	can be used to	add  unmatched
       lines to	the output. The	-v option can be used to output	only unmatched

       The default input field separators are blank, tab, or new-line. In this
       case,  multiple	separators  count  as one field	separator, and leading
       separators are ignored. The default output field	separator is a blank.

       If the input files are not in the appropriate collating	sequence,  the
       results are unspecified.

       Some  of	 the  options below use	the argument filenumber. This argument
       should be a 1 or	a 2 referring to either	file1 or file2,	respectively.

       -a filenumber	       In addition to the  normal  output,  produce  a
			       line  for each unpairable line in file filenum-
			       ber, where filenumber is	1 or 2.	If both	 -a  1
			       and  -a	2  are specified, all unpairable lines
			       will be output.

       -e string	       Replace empty output fields  in	the  list  se-
			       lected by option	-o with	the string string.

       -j fieldnumber	       Equivalent to -1fieldnumber -2fieldnumber.

       -j1 fieldnumber	       Equivalent to -1fieldnumber.

       -j2 fieldnumber	       Equivalent  to  -2fieldnumber.  Fields are num-
			       bered starting with 1.

       -o list		       Each output line	includes the fields  specified
			       in  list.  Fields  selected by list that	do not
			       appear in the input will	be  treated  as	 empty
			       output  fields.	(See the -e option.) Each ele-
			       ment of which has the either the	form  filenum-
			       ber.fieldnumber,	 or  0,	 which	represents the
			       join field. The common field is not printed un-
			       less specifically requested.

       -t char		       Use  character  char  as	a separator. Every ap-
			       pearance	of char	in a line is significant.  The
			       character  char	is used	as the field separator
			       for both	input and  output.  With  this	option
			       specified,  the	collating  term	 should	be the
			       same as sort without the	-b option.

       -v filenumber	       Instead of the default output, produce  a  line
			       only  for  each	unpairable line	in filenumber,
			       where filenumber	is 1 or	2. If both -v 1	and -v
			       2  are  specified, all unpairable lines will be

       -1 fieldnumber	       Join on the  fieldnumberth  field  of  file  1.
			       Fields are decimal integers starting with 1.

       -2fieldnumber	       Join  on	 the  fieldnumberth  field  of file 2.
			       Fields are decimal integers starting with 1.

       The following operands are supported:


       file2	A path name of a file to be joined. If either of the file1  or
		file2 operands is -, the standard input	is used	in its place.

       file1  and file2	must be	sorted in increasing collating sequence	as de-
       termined	by LC_COLLATE on the fields on which they are  to  be  joined,
       normally	the first in each line (see sort(1)).

       See  largefile(5)  for the description of the behavior of join when en-
       countering files	greater	than or	equal to 2 Gbyte (2**31	bytes).

       Example 1: Joining the password file and	group file

       The following command line will join the	password file  and  the	 group
       file,  matching on the numeric group ID,	and outputting the login name,
       the group name and the login directory. It is assumed  that  the	 files
       have been sorted	in ASCII collating sequence on the group ID fields.

       example%	join -j1 4-j2 3	-o 1.1 2.1 1.6 -t:/etc/passwd /etc/group

       Example 2: Using	the -o option

       The  -o	0  field essentially selects the union of the join fields. For
       example,	given file phone:

       !Name	       Phone Number
       Don	       +1 123-456-7890
       Hal	       +1 234-567-8901
       Yasushi	       +2 345-678-9012

       and file	fax:

       !Name	       Fax Number

       Don	       +1 123-456-7899

       Keith	       +1 456-789-0122

       Yasushi	       +2 345-678-9011

       where the large expanses	of white space are meant to each  represent  a
       single tab character), the command:

       example%	join -t"tab" -a	1 -a 2 -e '(unknown)' -o 0,1.2,2.2 phone fax

       would produce

       !Name	       Phone Number	      Fax Number
       Don	       +1 123-456-7890	       +1 123-456-7899
       Hal	       +1 234-567-8901	       (unknown
       Keith	       (unknown)	       +1 456-789-012
       Yasushi	       +2 345-678-9012	       +2 345-678-9011

       See  environ(5) for descriptions	of the following environment variables
       that affect the execution of join: LANG,	LC_ALL,	LC_CTYPE, LC_MESSAGES,

       The following exit values are returned:

       0	All input files	were output successfully.

       >0	An error occurred.

       See attributes(5) for descriptions of the following attributes:

       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       |Availability		     |SUNWcsu			   |
       |CSI			     |Enabled			   |
       |Interface Stability	     |Standard			   |

       awk(1),	comm(1),  sort(1),  uniq(1), attributes(5), environ(5),	large-
       file(5),	standards(5)

       With default field separation, the collating sequence is	that  of  sort
       -b; with	-t, the	sequence is that of a plain sort.

       The  conventions	 of  the  join,	sort, comm, uniq, and awk commands are
       wildly incongruous.

SunOS 5.10			  8 Feb	2000			       join(1)


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