The problem is that the order of the elements accessed from an array by the awk command:

Code:

for (index in array) {
        do stuff
}

is unspecified.

The index(string1, string2) function will return the position in string1 where string2 first appears (or 0 if string2 does not appear in string1). Since my code is checking that index() is returning 1, it is checking that string2 appears at the start of string1. If there are two entries in either of the master files where one key is an initial portion of another key in the same file, (such as USSDLIKE and US in your new master_1.txt), the following simple fix will work as long as the shorter key always follows the longer key in the master file. If you can't guarantee that the master files will follow this rule, we can change the script to sort the master files in reverse order before giving them to the awk script to get the desired results.

Note however, that it looks to me like your newly added line in inputfile:

Code:

US,261A,919143001234,8104738198,405899136999995,S,5

should be translated to:

Code:

Uninor,Silichar,261A,,KOL,8104738198,405899136999995,S,5

instead of to:

Code:

Uninor,Silichar,261A,,919143001234,8104738198,405899136999995,S,5

as you requested in message #3 in this thread because the field in red above should be converted due to the following entry in master_2.txt:

Code:

919143,KOL

Anyway, the awk script:

Code:

awk '
function FandR(fn, listindex, listindexcnt, list,       i) {
        for(i = 1; i <= listindexcnt; i++) {
                if(index($fn, listindex[i]) == 1) {
                        $fn = list[listindex[i]]
                        return
                }
        }
        if(fn < 3) $fn = $fn ","
}
BEGIN { FS = OFS = ","
}
FNR == 1 {
        fc++
}
fc == 1 {
        MASTERSPCGT[list1[++l1c] = $1] = $2 "," $3
        next
}
fc == 2 {
        MASTERMDNSERIES[list2[++l2c] = $1] = $2
        next
}
{       FandR(4, list2, l2c, MASTERMDNSERIES)
        FandR(3, list2, l2c, MASTERMDNSERIES)
        FandR(2, list1, l1c, MASTERSPCGT)
        FandR(1, list1, l1c, MASTERSPCGT)
        print
}' master_1.txt master_2.txt inputfile

uses list1[] (indexed by its line number in master_1.txt) and list2[] (indexed by its line number in master_2.txt) to store the keys. These lists can be used to check the keys in the order they were presented (instead of in an unspecified order).

The output from this script when given your updated input files is:

Code:

MTS,KRL,Airtel,DL,KOL,RAJ,919875089998,S,2
MTS,DEL,161A,,91225,8104738198,405899136999995,S,5
2A65,,919888799924,,DL,PUN,919875089998,S,1
MCA,,,,50009,8925682714,405899136999995,F,1
Uninor,Silichar,261A,,KOL,8104738198,405899136999995,S,5