MySQL查詢mysql_num_rows不工作

Question

這裏是code.Please幫助我的例子。

$query=mysql_query("set @row_count=0;SELECT *,@row_count := @row_count+1 as rank FROM users WHERE username='$username' "); 
$numrows=mysql_num_rows($query); 

Answer 1

嘗試在做ROW_NUMBER()功能的其他方式。見下圖：

$query=mysql_query("SELECT @row_count:=@row_count+1 AS rank, * FROM users, (SELECT @row_count:=0) AS A WHERE username='$username'"); 
$numrows=mysql_num_rows($query); 

Answer 2

只需使用：

$query=mysql_query("SELECT * , count(*) as rank FROM users WHERE username='$username' "); 
$numrows=mysql_num_rows($query);