You didn't happen to mention how the information in the second file was formatted (the one that has table names "ALONG WITH the database that they belong to"). If that second file is arranged as two "columns" (space-separated strings) per "row" (line), you might want to use hashes to make things easier: 
#!/usr/bin/perl

use strict;
use warnings;

my $table_list_file = shift;  # first command-line arg
my $table_db_list_file = shift;  # second arg

my %tables;
open( I, "<", $table_list_file ) or die "$table_list_file: $!";
while (<I>) {
    chomp;
    $tables{$_} = undef;
}
open( I, "<", $table_db_list_file ) or die "$table_db_list_file: $!";
while (<I>) {
    my ( $table_name, $db_name ) = split; # or maybe it's the other wa
+y around?
    if ( $tables{$table_name} ) { # seen in first file?
        print;
    }
}

[download]

And here's a shameless plug for an old post of mine: cmpcol would do this directly, given the following command line, if the files are like what I've assumed above: 

  cmpcol -i -l2 table.list table_db.list

[download]
In both cases suggested here, you can redirect STDOUT on the command line to create the output file that you want: 
  script.file [-options] file1 file2 > output.list

[download]

In reply to Re: comparing 2 files by graff
in thread comparing 2 files by dhudnall

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