my ($File_1_line,$File_2_line);
open(F1,"File_1");
open(F2,"File_2");

while($File_1_line=<F1>)
{
    #chomp $File_1_line;
    my @data=split(' ',$File_1_line);

    seek(F2,0,0);
    while($File_2_line=<F2>)
    {
      chomp $File_2_line;
      print "@data\n" if($data[0] eq $File_2_line);
    }


}

[download]

Try this it will help you.

In reply to Re: Merge two huge datasets by ID by leslie
in thread Merge two huge datasets by ID by dpangpang

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