ホームページ >バックエンド開発 >PHPチュートリアル >mysql 联合查询在数据库里测试时正确,通过php操作就不对了?
SQL语句如下:
"SELECT t.task_name,t.task_begin_p,t.task_end_p,t.task_end_r,p.proj_name from tasks as t inner join projects as p on t.task_project_id=p.proj_id where t.task_user_id=".$_SESSION['user_id']."order by t.task_begin_p ASC,t.task_end_p ASC;"
php代码如下:
<code>$link = mysqli_connect('localhost','root','root'); $db = mysqli_select_db($link,'workon'); mysqli_query($link,"set names 'utf8'"); $query = "SELECT t.task_name,t.task_begin_p,t.task_end_p,t.task_end_r,p.proj_name from tasks as t inner join projects as p on t.task_project_id=p.proj_id where t.task_user_id=".$_SESSION['user_id']."order by t.task_begin_p ASC,t.task_end_p ASC"; $data = mysqli_query($link,$query); while ($row = mysqli_fetch_assoc($data)) {};</code>
返回错误如下:
Warning: mysqli_fetch_assoc() expects parameter 1 to be mysqli_result, boolean given in
SQL语句如下:
"SELECT t.task_name,t.task_begin_p,t.task_end_p,t.task_end_r,p.proj_name from tasks as t inner join projects as p on t.task_project_id=p.proj_id where t.task_user_id=".$_SESSION['user_id']."order by t.task_begin_p ASC,t.task_end_p ASC;"
php代码如下:
<code>$link = mysqli_connect('localhost','root','root'); $db = mysqli_select_db($link,'workon'); mysqli_query($link,"set names 'utf8'"); $query = "SELECT t.task_name,t.task_begin_p,t.task_end_p,t.task_end_r,p.proj_name from tasks as t inner join projects as p on t.task_project_id=p.proj_id where t.task_user_id=".$_SESSION['user_id']."order by t.task_begin_p ASC,t.task_end_p ASC"; $data = mysqli_query($link,$query); while ($row = mysqli_fetch_assoc($data)) {};</code>
返回错误如下:
Warning: mysqli_fetch_assoc() expects parameter 1 to be mysqli_result, boolean given in
=".$_SESSION['user_id']."order by
这里,看到了吗?order by 前面没空格。
大神就是大神~~~楼上正解,想评论来着,搞错地方了