Yes, bind_columns/->fetchrow_arrayref (or its alias, ->fetch) is the fastest way to retrieve data, per the DBI docs:
[fetchrow_arrayref] Fetches the next row of data and returns a reference to an array holding the field values. Null fields are returned as undef values in the array. This is the fastest way to fetch data, particularly if used with $sth->bind_columns.
Perhaps the OP misread this as saying that the fastest option was fetchall_arrayref rather than fetchrow_arrayref?

The recommended technique, then, would be:

my $sth = $dbn->prepare("select number,id,start_dat,end_dat from SUBSC
+RIBERSLIST");
$sth->execute();
$sth->bind_columns(\$number, \$id, \$start_dat, \$end_dat);

my %hash =();
while ($sth->fetch) {
  # ->fetch populates the variables from ->bind_columns
  push @{$hash{$number}}, [$id, $start_dat, $end_dat];
};

$sth->finish();
$dbn->disconnect;

[download]

But, as already noted, you should also SELECT only the rows you need and do your processing line-by-line instead of sucking in the whole table at once if possible. I've only addressed the mechanics of how the OP is pulling the SELECTed rows.

In reply to Re^2: fastest method to use DBI by dsheroh
in thread fastest method to use DBI by Anonymous Monk

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