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awk NR==FNR compare 2 files produce a 3rd

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# 1  
Old 03-16-2009
awk NR==FNR compare 2 files produce a 3rd

hi, i have two files, both with 3 columns, the 3rd column has common values between the two files and i want to produce a 3rd file with 4 columns.

file 1

a, ,b c

file 2

a, b ,d

I want to compare the 3rd value and if a match print to file 3 with the 3 columns from the first file plus the entitlement column from file 2 added as 4th column , delimited.

file 3

a, b, c, d

I have been trying things like this borrowed off other posts but its outputing completely wrong, ive never really used awk that much

awk 'NR==FNR{x[$3]=$2;next}$3 in x&&$2=x[$3]' OFS="," FS="," file2 file1

Last edited by borderblaster; 03-18-2009 at 10:04 AM..
# 2  
Old 03-16-2009
nawk -F, '
{ if ( FILENAME == "file1" )
        _[$3]=_[$3]","$1 }
END { for ( i in _ ) print _[i] }
' file1 file2

# 3  
Old 03-17-2009
When I run this I get a syntax error, I only have awk on the server as well

awk -F, '{ if ( FILENAME == "file1.txt" )_[$3]=$0 else _[$3]=_[$3]","$1 }END { for ( i in _ ) print _[i] }' file1.txt file2.txt
awk: cmd. line:1: { if ( FILENAME == "file.txt" )_[$3]=$0 else _[$3]=_[$3]","$1 }END { for ( i in _ ) print _[i] }
awk: cmd. line:1: ^ syntax error
# 4  
Old 03-17-2009
Try this:

awk -F, 'NR==FNR{a[$3]=$1;next}$3 in a {$4=a[$3]}1' OFS="," file2 file1

Use nawk or /usr/xpg4/bin/awk on Solaris if you get errors.

# 5  
Old 03-17-2009
$ cat a.txt
cust1, ac1, 100
cust2, ac2, 200
$ cat b.txt
100000, cust1, 100
2000000, cust2, 200
$ join -a 1 -a 2 -1 3 -2 3 -t"," -o 1.1 1.2 1.3 2.1 a.txt b.txt
cust1, ac1, 100,100000
cust2, ac2, 200,2000000

Mind you, both files need to be sorted on the key column (stbid). In this case a.txt and b.txt are already sorted.

Last edited by rikxik; 03-17-2009 at 07:00 AM.. Reason: sort requirement
# 6  
Old 03-17-2009
franklin, ive realised i need to compare two columns, i.e. if both customer id and account id match in both files then append packageid to the end of the relevent line in the first file. Can that be done?
# 7  
Old 03-17-2009
Post an example of both files. You have not specify a colomn for the account id in your second file.


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