[b] if($key == ""){
$where = ' 1=1 ';
$model = Db::name('user');
}else{
$model = Db::name('user')->where("username|mempin",'like',"%$key%");
$this->assign('key',$key);
}

$count = $model->count();// 查询满足要求的总记录数
echo $model->getLastSql()."<br/>";
$Page = new Page($count,15);
$show = $Page->show();// 分页显示输出
$user = $model->limit($Page->firstRow.','.$Page->listRows)->order('id DESC')
->field("*")
->select();
echo $model->getLastSql();


打印出语句:
SELECT COUNT(*) AS tp_count FROM `hf_user` WHERE ( `username` LIKE '%sh%' OR `mempin` LIKE '%sh%' ) LIMIT 1

SELECT * FROM `hf_user` ORDER BY `id` DESC LIMIT 0,15

第二个语句中where条件丢失,请各位大神解惑,谢谢.