So I've got a big pile of tables in a mySQL database and I want to get a list of only the tables that have data; that is, I want to list all tables but those with zero rows. The best way I've been able to come up with to do this is the relatively ugly following code. There must be a better way! 
#Assuming $sth has just been executed with a "show tables" query
while(@tmp = $sth->fetchrow_array())
{
    my $tablename = $tmp[0];
    my $sth2 = $dbh->prepare("select count(*) from $tablename");
    $sth2->execute();
    $numrows = ($sth2->fetchrow_array())[0];
    if($numrows > 0)
    {
        push @tables, $tablename;
    }
}

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The whole having to create and execute another statement just seems... excessive. Non-perl like. It's especially pesky since DBI won't let me do something like this, which at least would allow me to call "prepare" only once: 
my $sth2 = $dbh->prepare("select count(*) from ?");
$sth2->execute($tablename);

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Apologies if this is more an SQL question than a perl question... I've poked around the DBI docs and haven't seen anything obvious.

In reply to DBI: Better way to find number of rows in a table? by anjiro

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