如果返回0行,MySQL返回结果

Question

我有这个PHP代码:

$query = "SELECT name, COUNT(message) FROM guestbook_message WHERE name='".$req_user_info['username']."' GROUP BY name"; 

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

while($row = mysql_fetch_array($result))
{
    echo "Messages posted: ". $row['COUNT(message)'] ."";
    echo "<br />";
}

这将显示用户发布的评论数量.

如果该用户没有发布消息,如何使其返回值？目前显示什么都没有.但我希望它显示"消息发布:0"

有任何想法吗？

Answer 1

检查结果中返回的结果数量mysql_num_rows.

$query = "SELECT name, COUNT(message) FROM guestbook_message WHERE name='".$req_user_info['username']."' GROUP BY name"; 

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

if(mysql_num_rows($result) > 0)
    while($row = mysql_fetch_array($result))
    {
       echo "Messages posted: ". $row['COUNT(message)'] ."";
       echo "<br />";
    }
else
    echo "NO Messages posted. <br />";