Try 
my $sql = "SELECT * FROM users WHERE id = ?";

my $statement = $db_handle->prepare($sql)
        or die "Couldn't prepare query '$sql': $DBI::errstr\n";

$statement->execute($user)
        or die "Couldn't execute query '$sql': $DBI::errstr\n";

[download]
If you really want to have $user in a string then you can add 
$user ||= '';

[download]
In your code before you use it.
-- gam3
A picture is worth a thousand words, but takes 200K.

In reply to Re: Dealing with uninitialized values by gam3
in thread Dealing with uninitialized values by shalomgod

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