Home  >  Article  >  Backend Development  >  mysql 联合查询在数据库里测试时正确,通过php操作就不对了?

mysql 联合查询在数据库里测试时正确,通过php操作就不对了?

WBOY
WBOYOriginal
2016-06-06 20:07:521094browse

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

回复内容:

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

Statement:
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn