Linux: Extract and transform attributes from line
문제
if got a file, with lines in the following format:
SOME_ATTRIBUTE_1 XYZ; IMPORTANT_ATTRIBUTE_1 1234; SOME_ATTRIBUTE_2 XYZ; IMPORTANT_ATTRIBUTE_2 AB;
Now I want to transform this into the following form, that the two important attribute values produce a new attribute:
JOIN_IMPORTANT_ATTRIBUTE AB1234; SOME_ATTRIBUTE_1 XYZ; IMPORTANT_ATTRIBUTE_1 1234; SOME_ATTRIBUTE_2 XYZ; IMPORTANT_ATTRIBUTE_2 AB;
Can this be done with some one-liner with awk or similar? I've got no idea how to tacle this, without grabbing into the java trickbox.
해결책
awk -F'[; ]+' '{print "JOIN_IMPORTANT_ATTRIBUTE", $8 $4 "; " $0}' file
다른 팁
With awk you can split the input at semi-colon + any number of spaces and further split the important fields like this:
awk -F'; *' '{ split($2, a1, / +/); split($4, a2, / +/); print "JOIN_IMPORTANT_ATTRIBUTE", a2[2] a1[2] ";", $0 }' infile
Output:
JOIN_IMPORTANT_ATTRIBUTE AB1234; SOME_ATTRIBUTE_1 XYZ; IMPORTANT_ATTRIBUTE_1 1234; SOME_ATTRIBUTE_2 XYZ; IMPORTANT_ATTRIBUTE_2 AB;
This assumes you know which columns the important attributes are in.
Perl solution:
perl -lane 'print join " ", "JOIN_IMPORTANT_ATTRIBUTE", substr($F[7], 0, -1) . $F[3], @F'
This is my bash+awk alternative.
cat attrs.awk
# Awk script to get joined attributes for one line of attributes
BEGIN {
RS=";";
PROCINFO["sorted_in"]="@ind_num_asc"; #gawk only: sort attributes on their attr id (so that IMPORTANT_ATTRIBUTE_n comes before IMPORTANT_ATTRIBUTE_n+1
}
$1 ~ /^IMPORTANT_ATTRIBUTE_/ {
attrId=substr($1, 1 + length("IMPORTANT_ATTRIBUTE_"));
if ($2 ~ /^[0-9]/)
impAttrsNum[attrId]=$2;
else
impAttrsAlpha[attrId]=$2;
}
END {
#alpha attribs come before num attribs
for(i in impAttrsAlpha)
alphaVals = alphaVals impAttrsAlpha[i];
for(i in impAttrsNum)
numVals = numVals impAttrsNum[i];
printf("JOIN_IMPORTANT_ATTRIBUTE %s%s%s", alphaVals, numVals, RS);
}
cat joinattrs
#!/bin/bash
#
# Applies joined attributes for each input line
while read l
do
if [[ -n "$l" ]]
then
joinAttrs=$(echo "$l" | awk -f attrs.awk)
echo "$joinAttrs $l"
fi
done
How to use it: ./joinattrs < datafile
Not a one-liner :)