[unix-history] / usr / man / man1 / join.1

.TH JOIN 1 
.SH NAME
join \- relational database operator
.SH SYNOPSIS
.B join
[
options
]
file1 file2
.SH DESCRIPTION
.I Join
forms, on the standard output,
a join
of the two relations specified by the lines of
.I file1
and
.IR file2 .
If
.I file1
is `\-', the standard input is used.
.PP
.I File1
and 
.I 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.
.PP
There is one line in the output 
for each pair of lines in 
.I file1 
and 
.I file2
that have identical join fields.
The output line normally consists of the common field,
then the rest of the line from 
.IR file1 ,
then the rest of the line from
.IR file2 .
.PP
Fields are normally separated by blank, tab or newline.
In this case, multiple separators count as one, and
leading separators are discarded.
.PP
These options are recognized:
.TP
.BI \-a n
In addition to the normal output,
produce a line for each unpairable line in file
.IR n ,
where
.I n
is 1 or 2.
.TP
.BI \-e \ s
Replace empty output fields by string
.IR s .
.TP
.BI \-j n\ m
Join on the
.IR m th
field of file
.IR n .
If
.I n
is missing, use the
.IR m th
field in each file.
.TP
.BI \-o \ list
Each output line comprises the fields specifed in
.IR list ,
each element of which has the form
.IR n . m ,
where
.I n
is a file number and
.I m
is a field number.
.PP
.TP
.BI \-t c
Use character
.I c
as a separator (tab character).
Every appearance of
.I c
in a line is significant.
.SH "SEE ALSO"
sort(1), comm(1), awk(1)
.SH BUGS
With default field separation,
the collating sequence is that of
.IR sort\ \-b ;
with
.BR \-t ,
the sequence is that of a plain sort.
.PP
The conventions of
.I join, sort, comm, uniq, look
and
.IR awk (1)
are wildly incongruous.
Commit	Line	Data
e6817382 BJ	1	.TH JOIN 1
	2	.SH NAME
	3	join \- relational database operator
	4	.SH SYNOPSIS
	5	.B join
	6	[
	7	options
	8	]
	9	file1 file2
	10	.SH DESCRIPTION
	11	.I Join
	12	forms, on the standard output,
	13	a join
	14	of the two relations specified by the lines of
	15	.I file1
	16	and
	17	.IR file2 .
	18	If
	19	.I file1
	20	is `\-', the standard input is used.
	21	.PP
	22	.I File1
	23	and
	24	.I file2
	25	must be sorted in increasing ASCII collating
	26	sequence on the fields
	27	on which they are to be joined,
	28	normally the first in each line.
	29	.PP
	30	There is one line in the output
	31	for each pair of lines in
	32	.I file1
	33	and
	34	.I file2
	35	that have identical join fields.
	36	The output line normally consists of the common field,
	37	then the rest of the line from
	38	.IR file1 ,
	39	then the rest of the line from
	40	.IR file2 .
	41	.PP
	42	Fields are normally separated by blank, tab or newline.
	43	In this case, multiple separators count as one, and
	44	leading separators are discarded.
	45	.PP
	46	These options are recognized:
	47	.TP
	48	.BI \-a n
	49	In addition to the normal output,
	50	produce a line for each unpairable line in file
	51	.IR n ,
	52	where
	53	.I n
	54	is 1 or 2.
	55	.TP
	56	.BI \-e \ s
	57	Replace empty output fields by string
	58	.IR s .
	59	.TP
	60	.BI \-j n\ m
	61	Join on the
	62	.IR m th
	63	field of file
	64	.IR n .
65	If
66	.I n
67	is missing, use the
68	.IR m th
69	field in each file.
70	.TP
71	.BI \-o \ list
72	Each output line comprises the fields specifed in
73	.IR list ,
74	each element of which has the form
75	.IR n . m ,
76	where
77	.I n
78	is a file number and
79	.I m
80	is a field number.
81	.PP
82	.TP
83	.BI \-t c
84	Use character
85	.I c
86	as a separator (tab character).
87	Every appearance of
88	.I c
89	in a line is significant.
90	.SH "SEE ALSO"
91	sort(1), comm(1), awk(1)
92	.SH BUGS
93	With default field separation,
94	the collating sequence is that of
95	.IR sort\ \-b ;
96	with
97	.BR \-t ,
98	the sequence is that of a plain sort.
99	.PP
100	The conventions of
101	.I join, sort, comm, uniq, look
102	and
103	.IR awk (1)
104	are wildly incongruous.