sub open_dbi {
   my $db_user = $DBuser;
   my $db_password = $DBpassword;
   my $DBName = 'db';
   my $dbh = DSBI->connect("dbi:mysql:DBName:$IP","$db_user","db_password";
   return $dbh;
}

This part writes the sql command to the table:

sub write_db {
   $SQLCommand = "{SQL command}";
   my $sth = $dbh->prepare("$SQLCommand");
   $sth->execute;
}