Be careful: in a multi-user database, someone can insert the row between the select and insert statements. A better way to do this is to combine the existence test with the insert: 

my $sql = qq{
if not exists
    (select 1 from members where username = ?)
insert into members
    (username, password, email, name, url, date)
values (?, ?, ?, ?, ?, ?)
};
my $sth = $dbh->prepare($sql);
$sth->execute($username, $username,
    $password, $email, $name, $url, $date)

[download]
Note that $username appears twice, the first one to bind to the existence test. (BTW, I haven't tested this, and I'm assuming MySQL supports prepared exists clauses.)

In reply to Re: Re: mySQL with Perl by VSarkiss
in thread mySQL with Perl by skirrow

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