One reason it's so slow is that you're loading the
entire database table into your program, when you
only need 3 lines! You don't need to do that; since
you're using MySQL, you can use the LIMIT
directive:
select foo from bar limit 3
What do you want that where clause to do? That
matches *any* ID: so you don' t need it. Just
eliminate the where clause entirely.
And why are you selecting three columns if you
only want one? Just say
select data from frog limit 3
Also you should try using bind_columns and
fetch, cause it's faster:
my($data);
$sth->bind_columns(\$data);
while ($sth->fetch) {
print $data;
}
If you want to select multiple columns, try this:
my $sth = $dbh->prepare(<<SQL);
select id, data from frog limit 3
SQL
$sth->execute;
my($id, $data);
$sth->bind_columns(\$id, \$data);
while ($sth->fetch) {
print $id, "\t", $data, "\n";
}
(By the way, I took out the error-checking partly
for brevity, and partly cause I always use RaiseError).
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