Shell Programming and Scripting

XX,ZZ,XC,EE,RR,BB
XC,CF,FG,RG,GH,GH

DF,GH,MH,FR,FG,GH,NOTOK
XX,ZZ,XC,EE,RR,BB,OK

XX,ZZ,XC,EE,RR,BB  OK

XX,ZZ,XC,EE,RR,BB  OK,OK

for n in `cat /tmp/file1.txt |awk -F "," '{print $1}'`
do
exec 3< /tmp/file1.txt  while read -u3 line ; do
r=`cat /tmp/file2.txt |grep -i $n |awk -F "," '{print $7}'`
s1=`cat /tmp/file1.txt|grep -i $n |awk -F "," '{print $1}'`                                                                           
s2=`cat /tmp/file1.txt|grep -i $n |awk -F "," '{print $2}'`
s3=`cat /tmp/file1.txt|grep -i $n |awk -F "," '{print $3}'`
s4=`cat /tmp/file1.txt|grep -i $n |awk -F "," '{print $4}'`
echo $s1"," $s2 "," $s3 "," $s4 "," $r ","
done

awk -F, '{$(NF+1)=++i;}1' OFS=, file

awk -f vlookup.awk file2.txt file1.txt 
cat vlookup.awk
FNR==NR{
  a[$1]=$1
  next
}
{ if ($1 in a) {print $1 $2 $3 $4, a[$3]} else {print $1 $2 $3 $4 , "NA"}  }

 
 awk -F',' 'NR==FNR{a[$1]=$0;next} $1 in a {print a[$1]" "$7}' file1 file2 > file3

 
 awk -F',' 'NR==FNR{a[$1]=$0;next} $1 in a {print a[$1]","$7}'  file3 file2

 
 $ cat > tmp1
 XX,ZZ,XC,EE,RR,BB
 XC,CF,FG,RG,GH,GH
 　
 $ cat > tmp2
 DF,GH,MH,FR,FG,GH,NOTOK
 XX,ZZ,XC,EE,RR,BB,OK
 　
  
 $ awk -F',' 'NR==FNR{a[$1]=$0;next} $1 in a {print a[$1]" "$7}' tmp1 tmp2
 XX,ZZ,XC,EE,RR,BB OK
  
 $ awk -F',' 'NR==FNR{a[$1]=$0;next} $1 in a {print a[$1]" "$7}' tmp1 tmp2 > tmp3
  
 $ awk -F',' 'NR==FNR{a[$1]=$0;next} $1 in a {print a[$1]","$7}' tmp3 tmp2
 XX,ZZ,XC,EE,RR,BB OK,OK

XX,ZZ,XC,EE,RR,BB,OK 
XC,CF,FG,RG,GH,GH,NA

                                                    Day1,Day2
XX,ZZ,XC,EE,RR,BB,OK,NA
 XC,CF,FG,RG,GH,GH,NA,OK

 XX,ZZ,XC,EE,RR,BB 
XC,CF,FG,RG,GH,GH

 DF,GH,MH,FR,FG,GH,NOTOK 
XX,NM,XC,EE,RT,BB,OK

XX,ZZ,XC,EE,RR,BB,OK -- > since xx in both file1,file2 in first column matches 
XC,CF,FG,RG,GH,GH,NA --->since XC in file1 is not having entry as first column in f, ile 2 so how to display as NA

XX,ZZ,XC,EE,RR,BB,OK,OK
XC,CF,FG,RG,GH,GH,NA,NA