[unix-history] / usr / src / usr.bin / join / join.1

.\"	@(#)join.1	6.1 (Berkeley) %G%
.\"
.TH JOIN 1 ""
.AT 3
.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 specified 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
765a0daa	1	.\" @(#)join.1 6.1 (Berkeley) %G%
9aaec80d	2	.\"
765a0daa	3	.TH JOIN 1 ""
9aaec80d KM	4	.AT 3
	5	.SH NAME
	6	join \- relational database operator
	7	.SH SYNOPSIS
	8	.B join
	9	[
	10	options
	11	]
	12	file1 file2
	13	.SH DESCRIPTION
	14	.I Join
	15	forms, on the standard output,
	16	a join
	17	of the two relations specified by the lines of
	18	.I file1
	19	and
	20	.IR file2 .
	21	If
	22	.I file1
	23	is `\-', the standard input is used.
	24	.PP
	25	.I File1
	26	and
	27	.I file2
	28	must be sorted in increasing ASCII collating
	29	sequence on the fields
	30	on which they are to be joined,
	31	normally the first in each line.
	32	.PP
	33	There is one line in the output
	34	for each pair of lines in
	35	.I file1
	36	and
	37	.I file2
	38	that have identical join fields.
	39	The output line normally consists of the common field,
	40	then the rest of the line from
	41	.IR file1 ,
	42	then the rest of the line from
	43	.IR file2 .
	44	.PP
	45	Fields are normally separated by blank, tab or newline.
	46	In this case, multiple separators count as one, and
	47	leading separators are discarded.
	48	.PP
	49	These options are recognized:
	50	.TP
	51	.BI \-a n
	52	In addition to the normal output,
	53	produce a line for each unpairable line in file
	54	.IR n ,
	55	where
	56	.I n
	57	is 1 or 2.
	58	.TP
	59	.BI \-e \ s
	60	Replace empty output fields by string
	61	.IR s .
	62	.TP
	63	.BI \-j n\ m
	64	Join on the
	65	.IR m th
	66	field of file
	67	.IR n .
68	If
69	.I n
70	is missing, use the
71	.IR m th
72	field in each file.
73	.TP
74	.BI \-o \ list
c72499ab	75	Each output line comprises the fields specified in
9aaec80d KM	76	.IR list ,
	77	each element of which has the form
	78	.IR n . m ,
	79	where
	80	.I n
	81	is a file number and
	82	.I m
	83	is a field number.
	84	.PP
	85	.TP
	86	.BI \-t c
	87	Use character
	88	.I c
	89	as a separator (tab character).
	90	Every appearance of
	91	.I c
	92	in a line is significant.
	93	.SH "SEE ALSO"
	94	sort(1), comm(1), awk(1)
	95	.SH BUGS
	96	With default field separation,
	97	the collating sequence is that of
	98	.IR sort\ \-b ;
	99	with
	100	.BR \-t ,
	101	the sequence is that of a plain sort.
	102	.PP
	103	The conventions of
	104	.I join, sort, comm, uniq, look
	105	and
	106	.IR awk (1)
	107	are wildly incongruous.