根据第一列将多个具有不等行/行的管道分隔文件连接到一个文件中。
前任：
测试1.txt
1|1
2|2
测试2.txt
1|4
2|5
3|6
测试3.txt
1|7
2|8
3|9
4|10
输出：
1|1|4|7
2|2|5|8
3||6|9
4|||10
示例2：test1.txt
1|1|2
2|3|4
测试2.txt
1|4
2|5
3|6
测试3.txt
1|7
2|8
3|9
4|10
输出：
1|1|2|4|7
2|3|4|5|8
3||||6|9
4|||||10
答案1
仅适用于所示情况，每个文件中有两列和三个文件：
$ join -t '|' -o0,1.2,2.2 -a 1 -a 2 test[12].txt | join -t '|' -o0,1.2,1.3,2.2 -a 1 -a 2 - test3.txt
1|1|4|7
2|2|5|8
3||6|9
4|||10
也就是说，对前两个文件执行关系完全外连接，并以相同的方式将其输出与第三个文件连接。正是它-a 1 -a 2使其成为完整的外部连接。使用 GNU join，您可以将-o选项及其选项参数替换为-o auto.
这可以概括为脚本：
#!/bin/sh
# sanity check
if [ "$#" -lt 2 ]; then
echo 'require at least two files' >&2
exit 1
fi
# temporary files
result=$(mktemp) # the result of a join
tmpfile=$(mktemp) # temporary file holding a previous result
# remove temporary files on exit
trap 'rm -f "$result" "$tmpfile"' EXIT
# join the first two files
join -t '|' -o auto -a 1 -a 2 "$1" "$2" >"$result"
shift 2
# loop over the remaining files, adding to the result with each
for pathname do
mv "$result" "$tmpfile"
join -t '|' -o auto -a 1 -a 2 "$tmpfile" "$pathname" >"$result"
done
# done, output result
cat "$result"
该脚本依赖于 GNU 的join选项-o auto，并且假设连接将发生在|每个文件中的第一个 - 分隔字段上，并且文件在此字段上按字典顺序排序。
它连接前两个文件，然后添加到该连接的结果，每个剩余文件一次。
问题中的第一个例子：
$ ./script.sh test[123].txt
1|1|4|7
2|2|5|8
3||6|9
4|||10
问题中的第二个示例（请注意，在问题中，显示了错误数量的空字段）：
$ ./script.sh test[123].txt
1|1|2|4|7
2|3|4|5|8
3|||6|9
4||||10
如果文件未排序，那么您可以随时对它们进行排序（注意：切换到bash此处进行进程替换）：
#!/bin/bash
# sanity check
if [ "$#" -lt 2 ]; then
echo 'require at least two files' >&2
exit 1
fi
# temporary files
result=$(mktemp) # the result of a join
tmpfile=$(mktemp) # temporary file holding a previous result
# remove temporary files on exit
trap 'rm -f "$result" "$tmpfile"' EXIT
# join the first two files
join -t '|' -o auto -a 1 -a 2 \
<( sort -t '|' -k1,1 "$1" ) \
<( sort -t '|' -k1,1 "$2" ) >"$result"
shift 2
# loop over the remaining files, adding to the result with each
for pathname do
mv "$result" "$tmpfile"
# note: $tmpfile" would already be sorted
join -t '|' -o auto -a 1 -a 2 \
"$tmpfile" \
<( sort -t '|' -k1,1 "$pathname" ) >"$result"
done
# done, output result
cat "$result"
要允许用户连接另一个字段（使用-f），请使用另一个分隔符（使用-d），并使用另一个连接类型（使用-j），
#!/bin/bash
# default values
delim='|'
field='1'
join_type=( -a 1 -a 2 ) # full outer join by default
# override the above defaults with options given to us by the user
# on the command line
while getopts 'd:f:j:' opt; do
case "$opt" in
d) delim="$OPTARG" ;;
f) field="$OPTARG" ;;
j)
case "$OPTARG" in
inner) join_type=( ) ;;
left) join_type=( -a 1 ) ;;
right) join_type=( -a 2 ) ;;
full) join_type=( -a 1 -a 2 ) ;;
*) printf 'unknown join type "%s", expected inner, left, right or full\n' "$OPTARG" >&2
exit 1
esac ;;
*) echo 'error in command line parsing' >&2
exit 1
esac
done
shift "$(( OPTIND - 1 ))"
# sanity check
if [ "$#" -lt 2 ]; then
echo 'require at least two files' >&2
exit 1
fi
# temporary files
result=$(mktemp) # the result of a join
tmpfile=$(mktemp) # temporary file holding a previous result
# remove temporary files on exit
trap 'rm -f "$result" "$tmpfile"' EXIT
# join the first two files
join -t "$delim" -j "$field" -o auto "${join_type[@]}" \
<( sort -t "$delim" -k"$field,$field" "$1" ) \
<( sort -t "$delim" -k"$field,$field" "$2" ) >"$result"
shift 2
# loop over the remaining files, adding to the result with each
for pathname do
mv "$result" "$tmpfile"
# note: $tmpfile would already be sorted and
# the join field is the first field in that file
join -t "$delim" -2 "$field" -o auto "${join_type[@]}" \
"$tmpfile" \
<( sort -t "$delim" -k "$field,$field" "$pathname" ) >"$result"
done
# done, output result
cat "$result"
通过重新运行第二个示例进行测试：
$ ./script.sh test[123].txt
1|1|2|4|7
2|3|4|5|8
3|||6|9
4||||10
在相同的文件上运行，但在第二个字段上加入：
$ ./script.sh -f 2 test[123].txt
1|1|2||
10||||4
3|2|4||
4|||1|
5|||2|
6|||3|
7||||1
8||||2
9||||3
进行内连接：
$ ./script.sh -j inner test[123].txt
1|1|2|4|7
2|3|4|5|8
答案2
使用 GNU awk 和你的第二组测试数据
BEGIN { FS = OFS = "|" }
# like the shell's shift function, returns the "former" first field
function shift( value, i) {
value = $1
for (i=1; i<NF; i++) $i = $(i+1)
NF--
return value
}
# return a string with a character repeated n times
# repeat("x", 5) ==> "xxxxx"
function repeat(char, n, str) {
str = sprintf("%*s", n, "")
gsub(/ /, char, str)
return str
}
FNR == 1 {fn++; nf[fn] = NF - 1}
{
key = shift()
data[fn][key] = $0
seen[key]
}
END {
for (key in seen) {
printf "%s", key
for (f=1; f<=fn; f++) {
if (key in data[f])
row = data[f][key]
else
row = repeat(FS, nf[f] - 1)
printf "%s%s", FS, row
}
print ""
}
}
然后
gawk -f joiner.awk test{1,2,3}.txt
1|1|2|4|7
2|3|4|5|8
3|||6|9
4||||10