Hello everyone, here's the scenario

I have two files, each one has around 1,300,000 lines and each line has a column (phone numbers). I have to get the phones that are in file1 but not in file2. I can get these phones trough Oracle but my boss does not want that so he gave me the files with the phone numbers (he said it will take hours to finish the query and that will reduce the server resources or something like that).

First I tried to solve the problem with some perl scripting but it took like 10 minutes just to read the files and because my poor programming skills i tried to do the search with a double foreach, something like this:

@file1 = <SOME1>;
@file2 = <SOME2>;
$n = 0;
$flag = true; #if $flag = false then the element is in file2

foreach $row1 (@file1)
{
foreach $row2 (@file2)
{
if($row1 == $row2)
$flag = false
}
if($flag)
{
$anArray[$n]\=$row1; #ignore the backslash please
$n++;
}
$flag = true;
}

if($n > 0)
{
foreach $row3 (@anArray)
{
print OUT_FILE "$row3\n";
}
}



The data from the files is like this:


FILE1
----------------------------
1234567890
0987654321
2345678901
9012345678


FILE2
----------------------------
1234567890
0987654321
2345678901


OUT_FILE must be
----------------------------
9012345678



but this solution wil take ages to finish so now i am thinking in using awk or another lenguage but i really don't know which one is better for this problem and what algorithm i should use (besides i have never used awk or shell scripting, I'm new using UNIX), I was thinking in sort the files and then do a binary search but i have some doubts about it so i feel really lost now

Thanks for your help