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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
			       selected	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
			       unless specifically requested.

       -t char		       Use   character	char  as  a  separator.	 Every
			       appearance of char in a	line  is  significant.
			       The character char is used as the field separa-
			       tor 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
       determined  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
       encountering 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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