Hi everyone!

I've a code reading a very big SQL result froma MySQL database: 

my $query = $self->{dbh}->prepare("select * from $database.$self->{hit
+_table} where time between ? and ? order by visit_id, time", {'mysql_
+use_result' => $self->{optimize}});
$query->execute($start_time + 0, $end_time + 0);
while (my $row = $query->fetchrow_hashref())
{
   # Do calculation
}

[download]

The problem is with the fetchrow_hashref, it take too long and I've a:
DBD::mysql::st fetchrow_hashref failed: Lost connection to MySQL serve
+r during query

[download]

the query returns something like 10M of rows from a DB with more than 150M and it takes at least 1 hour.

My question is: Which is the most performance methode to fetch so big results?
The difference between a fetchrow and a fetchall methode?

TIA

In reply to fetchrow and fetchall question by Anonymous Monk

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