目前,如果用户填写表单并输入已在使用的用户名,则会在新页面上显示MySQL error Duplicate entry 'fred' for key 'username'。$username_entry = ($_POST['username']);
$username_match = mysql_query("SELECT * FROM business WHERE username
警告: mysql_num_rows()期望参数1是第x行的资源。我检查了所有丢失的单引号和sql链接。$query_1 = sprintf("select part_of_speech_id from word_parts_of_speech where word = '%s'", mysql_real_escape_string($v)); if(mysql_num_rows($re