Question

如何制作这样的东西（在SELECT命令中添加内容）：

 $query = "SELECT a.name,a.surname,b.email,c.phone 
           FROM users as a 
           inner join users_email as b 
           inner join users_phone as c
           WHERE a.id=b.id AND a.id=c.id";

 $query .= "ORDER BY a.surname";  

 $result = mysql_query($query,$con);

结果应为：

$query = "SELECT a.name,a.surname,b.email,c.phone 
          FROM users as a 
          inner join users_email as b 
          inner join users_phone as c
          WHERE a.id=b.id AND a.id=c.id
          ORDER BY a.name";   

$result = mysql_query($query,$con);
$row=mysql_num_fields($result)

...但是它给出了一个错误：mysql_num_fields（）期望参数1是资源，布尔值在第32行的C：\ xampp-portable \ htdocs \ db \ file.php中给出...

Answer 1

在连接查询时始终提供space。

 $query = "SELECT a.name,a.surname,b.email,c.phone 
           FROM users as a 
           inner join users_email as b 
           inner join users_telefon as c
           WHERE a.id=b.id AND a.id=c.id ";

 $query .= " ORDER BY a.prenume";
            ^

还要练习mysql_error()。

$result = mysql_query($query,$con) or die(mysql_error());

注意： Please, don't use mysql_* functions in new code。它们不再被维护and are officially deprecated。请参阅red box？转而了解prepared statements，并使用PDO或MySQLi - this article将帮助您确定哪个。如果您选择PDO here is a good tutorial。

Answer 2

在

之后添加空格

WHERE a.id=b.id AND a.id=c.id";

所以它应该是：

WHERE a.id=b.id AND a.id=c.id ";

Answer 3

试试这个：

$query = "SELECT a.name,a.surname,b.email,c.phone 
           FROM users as a 
           inner join users_email as b 
           inner join users_telefon as c
           WHERE a.id=b.id AND a.id=c.id";

 $query .= " ORDER BY a.prenume";  

 $result = mysql_query($query,$con);

在订购依据

之前需要'空格'

Answer 4

$query = "SELECT a.name,a.surname,b.email,c.phone 
          FROM users as a 
          inner join users_email as b ON a.id=b.id
          inner join users_telefon as c ON a.id=c.id
          ORDER BY a.name";

Answer 5

应该是

 $query .= " ORDER BY a.prenume order(asc/desc)";

而不是

 $query .= "ORDER BY a.prenume";

你需要在ORDER BY

之前给出空格

php mysql add * to SELECT语句

5 个答案: