#!/usr/local/bin/perl -wd

my $DBS = {DB1=>1,DB2=>1,Q=>1};

my $db = select_db($DBS);

sub select_db {
   my( $dbs ) = shift;
   my( $adb );

   while(1) {
      print "Select a database: ";
      $adb = <STDIN>;
      chomp($adb);
      last if $dbs->{uc $adb};
   }
   $adb;
}
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