Question

我在我的第5页查询中，如果可能的话，我希望只有一个查询，我不知道是否有一个更好的策略，我正在做什么或它的确定。

这是我加载图书的主要查询

 $mess = $mysqli->prepare('SELECT * from ( SELECT m.id, cm.voteup,
                                                  cm.votedown,cr.book_descr FROM books m
                           INNER JOIN  books_vote cm ON cm.bookid = m.id
                           INNER JOIN  book_info cr ON cr.bookid = m.id
                           WHERE bookid = ?  ORDER BY m.date DESC LIMIT 30)ddd 
                           ORDER BY m.date ASC');
    $mess->bind_param("i", $book);                              
    $mess->execute();
    $mess->store_result();
    $mess->bind_result($id,$voteup,$votedown);
        while($row = $mess->fetch()){
             //  im fetching here in this <div class='areabooks'>  
              }

然后我重置查询以获取其他具有IF条件的div

  $mess->data_seek(0);
  while($row = $mess->fetch()){
    if($voteup - $votedown >= 5){
      //I fetch here in this <div class='areabooks2'>
        }
        }

然后我使用此查询检查顶部MAX(voteup - votedown )

 $messtop = $mysqli->prepare('SELECT ..........
                           INNER JOIN ...
                           INNER JOIN ( select id ,MAX(voteup - votedown ) as maxe
                                from books
                                where voteup - votedown >= 5
                                group by id  ) tt
                           WHERE bookid = ?
                           ORDER BY maxe DESC,cm.votedown asc,cm.voteup DESC
                           limit 1');
    $messtop->bind_param("i", $book);                              
    $messtop->execute();
    $messtop->store_result();
    $messtop->bind_result($id,$voteup,$votedown);
    $messtop->fetch();
    // then i fetch in this <div class='topbook' >

然后我再次重置第一个查询以获取其他具有IF条件的div

$mess->data_seek(0); 
while($row = $mess->fetch()){
    if($votedown - $voteup >= 5){
       //I fetch here in this <div class='areabooks3' >
    }
}

然后我使用此查询获取顶部MAX(votedown - voteup )

   $messtop = $mysqli->prepare('SELECT ..........
                           INNER JOIN ...
                           INNER JOIN ( select id ,MAX(votedown - voteup) as maxe
                                from books where votedown - voteup >= 5
                                group by id  ) tt
                           WHERE bookid = ?
                           ORDER BY maxe DESC,cm.voteup ASC,cm.votedown DESC
                           limit 1');
    $messdown->bind_param("i", $book);                              
    $messdown->execute();
    $messdown->store_result();
    $messdown->bind_result($id,$voteup,$votedown);
    $messdown->fetch();
    // then i fetch in this <div class='topbottonbook' >

我正在寻找的是，如果有一个策略只使用一个查询并在所有这些div中获取它，那些div就像那样分开。

 <first div>
 <second div>
 <3rd div>
 <4th div>
  5th div

如何简化此感谢？

Answer 1

我怀疑3个查询是否可以组合成一个。

首先查询：

推迟JOIN，直到您获得30个'最新'bookids。也就是说，将JOIN移到外部SELECT。

也有INDEX(id, date)。但我很困惑。通常id是PRIMARY KEY，因此是唯一的。但查询暗示一本书有多个日期。是什么赋予了？（请提供SHOW CREATE TABLE。）

mysql命令行工具（或Workbench或phpmyadmin）是你的朋友。使用其中一个手动运行查询。我想你会发现错误。请修理。

第

1 个答案: