Mysql 查询 mysql_num_rows 不起作用

Question

这是示例代码。请帮助我。

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

Answer 1

尝试用其他方式执行ROW_NUMBER()函数。见下文:

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