bool(false)
<br/><br />
<b>Warning</b>:  mysql_num_rows() expects parameter 1 to be resource, boolean given in <b>/var/www/html/2016/kezhy/Chapter9/select.php</b> on line <b>8</b><br />
student表的记录数为：<br />
<b>Warning</b>:  mysql_free_result() expects parameter 1 to be resource, boolean given in <b>/var/www/html/2016/kezhy/Chapter9/select.php</b> on line <b>9</b><br />