This is untested, but there are comments you may find helpful in the code. 

#!/usr/bin/perl

use warnings;
use strict;
use DBI;

my $dbh;

#A lexical scope so that the db... variables go out of scope quickly.
{
        my $dbname = "database";
        my $dbuser = "user";
        my $dbpass = "password";
        my $dbhost = "localhost";
        my $dbport = 3306;
        my $dsn    = "DBI:mysql:database=$dbname;host=$dbhost;port=$db
+port";
        $dbh = DBI->connect($dsn, $dbuser, $dbpass, {  RaiseError => 1
+ })
                or die "Couldn't connect to the database: $!\n";
}


#Use placeholders here. Your DBD driver will then take care of
#appropriate quoting.
my $sth = $dbh->prepare("SELECT ID, Data FROM table_name WHERE Data=?"
+);
$sth->execute("value");


#You're executing the update query lots of times.
#Prepare it once, then execute it with different values.

my $update_sth = $dbh->prepare("UPDATE new_table SET newData=? WHERE n
+ewID=?");

#No point doing the looping over your DataHash twice, you've got the d
+ata
#once, why not use it here?
while(my ($id, $data) = $sth->fetchrow) {
        $update_sth->execute($data, $id);
}

#I never bother with these if it's at the end of a script personally.
#They'll happen automatically when the variables get DESTROY'ed
$sth->finish;
$update_sth->finish;
$dbh->disconnect;

[download]

davis
It's not easy to juggle a pregnant wife and a troubled child, but somehow I managed to fit in eight hours of TV a day.

In reply to Re: How to Speed up MySQL w/ Perl by davis
in thread How to Speed up MySQL w/ Perl by rsiedl

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