.TH difference "" "" "/rdb Command"
.PC "Output table of rows that are in only one table"
\fBdifference \fItable1 table2\fR
.PP
.II table^difference
.II table^subtract
.II "subtract tables"
.II sort
.II uniq
The command
.B difference
uses the COHERENT commands
.B sort
and
.B uniq
to subtract logically
.I table2
from
.IR table1 .
Its output consists of the rows that are in
.I table1
but not in
.IR table2 .
The two input tables must have the same columns
(\fIunion compatible\fR in the technical data-base literature),
and the rows must be exactly identical \(em including every space, tab,
and nonprinting character.
If two rows look the same to you but not to
.BR difference ,
try the
.B see
command to discover any blank spaces and nonprinting characters.
.SH Example
In this example, consider the table
.BR journal ,
which appears as follows:
.DM
Date    Amount  Account Ref     Description
------- ------- ------- ------- --------------------------------
820107    14.00 meal    v       meal with jones
820113   101.62 car     v       car repairs
820114    81.80 insur   c       car insurance allstate
820114    93.00 car     c       car registration dmv
820119    81.72 vitamin c       sundown vitamins
820121    20.83 meal    v       meal with scott
820121  2500.00 keogh   c       keogh payment
820125    99.00 dues    v       dues to uni-ops unix conference
.DE
.PP
And consider the table
.BR carexpense ,
which appears as follows:
.DM
Date    Amount  Account Ref     Description
------- ------- ------- ------- --------------------------------
820113   101.62 car     v       car repairs
820114    81.80 insur   c       car insurance allstate
820114    93.00 car     c       car registration dmv
.DE
.PP
The command
.DM
	difference journal carexpense
.DE
.PP
logically ``subtracts''
.B carexpense
from
.BR journal ,
to produce the following output:
.DM
Date    Amount  Account Ref     Description
------- ------- ------- ------- --------------------------------
820107    14.00 meal    v       meal with jones
820119    81.72 vitamin c       sundown vitamins
820121    20.83 meal    v       meal with scott
820121  2500.00 keogh   c       keogh payment
820125    99.00 dues    v       dues to uni-ops unix conference
.DE
.SH "See Also"
COHERENT Lexicon:
.B
diff,
diff3,
sort,
uniq
.R
.SO difference