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Php 我能';我似乎无法让这个sql查询按我想要的方式工作_Php_Mysql_Sql_Mysqli_Phpmyadmin - Fatal编程技术网

Php 我能';我似乎无法让这个sql查询按我想要的方式工作

Php 我能';我似乎无法让这个sql查询按我想要的方式工作,php,mysql,sql,mysqli,phpmyadmin,Php,Mysql,Sql,Mysqli,Phpmyadmin,我有一张桌子,上面有一些书籍的评级 我创建了一些虚拟记录来测试这个查询 ID BookID RatersID Rating Date 1 2 3 5 (date) 2 2 4 4 (date) SELECT `RatersID`, COUNT(*) AS `raters`, `Rating`, COUNT(*) AS `Ratings` FRO

我有一张桌子,上面有一些书籍的评级

我创建了一些虚拟记录来测试这个查询

 ID    BookID   RatersID     Rating    Date
 1     2        3            5         (date)
 2     2        4            4         (date)


SELECT `RatersID`,
COUNT(*) AS `raters`, `Rating`, COUNT(*) AS `Ratings`
FROM
`BOOKS_ratings`
GROUP BY
`BookID`
当我运行我期望的查询时

BookID    Raters     Ratings
2         2          9
我得到的是:

RatersID    raters    Rating    Ratings
3           2         5         2
我不明白为什么会这样? ///////////////////以上问题已得到答复

我已经让查询工作,但当试图在php中接收信息的数字是重复的

例如,评分员=2 PHP显示22 评级=9 PHP显示99

    $getratingq = mysqli_query($con,"SELECT `RatersID`, COUNT(*) AS `Raters`, sum(Rating) AS `Ratings` FROM `BOOKS_ratings` WHERE `BookID` ='$bookid' GROUP BY `BookID` LIMIT 1") or die("Get ratings query error");
if($getrating = mysqli_fetch_array($getratingq))
{
   echo $ratings = $getrating['Ratings'];
   $raters= $getrating['Raters'];
   $rating =  $ratings/$raters;
   $stars = floor("$rating");
}
您需要使用
sum()
来获得评级的总和

    SELECT 
   `BookID`,
    COUNT(*) AS `raters`
    sum(Rating) as Ratings
    FROM
    `BOOKS_ratings`
    GROUP BY
    `BookID`

谢谢你,我意识到了我的错误,我使用了计数来计算有多少人被评分,而不是我应该使用总数