I have two files with tab-separated values that look like this:
file1:
A 1
B 3
C 1
D 4
file2:
E 1
B 3
C 2
A 9
I would like to find rows between files 1 and 2 where the string in column 1 is the same, then get the corresponding values. The desired output is a single file that looks like this:
B 3 3
C 1 2
A 1 9
Can this be done with a Unix one-liner?
GNU coreutils includes the command join that does exactly what you want if line sorting in the result is irrelevant:
join <(sort file1) <(sort file2)
A 1 9
B 3 3
C 1 2
If you want the tabs back, do:
join <(sort file1) <(sort file2) | tr ' ' '\t'
A 1 9
B 3 3
C 1 2
Or use the t option to join.
(<() aka process substitution, requires ksh93 (where the feature originated in), bash or zsh)
ire@localhost: sort -k1 file2 | join file1 -
A 1 9
B 3 3
C 1 2
If you want tabs in the output, then do
sort -k1 file2 | join -t " " file1 -
where you can construct the tab inside the quotes by pressing CTRL-V <tab>.
If you don't want the output sorted but instead have the same order as file2, awk is a good tool to use:
awk '
NR == FNR {val[$1]=$2; next}
$1 in val {print $1, val[$1], $2}
' file1 file2
