如何避免多次呼叫我的数据库?(MySQL+PHP)


How to avoid the numerous calls to my DB? (MySQL + PHP)

使用以下代码,我可以使用FQL在Facebook上管理所有页面。不过我不打印它们。

$PageNames = $facebook->api('/fql', array('q' => 
        'SELECT name, page_id FROM page WHERE page_id IN (
               SELECT page_id FROM page_admin  WHERE  uid=me() )'));

以前,我在数据库中添加了一些页面的*page_id*。我的目标是显示尚未添加到数据库中的页面。它工作正常,代码如下。

  foreach($PageNames['data'] as $PageName) {
    $investigate_id = mysql_query("SELECT page_id FROM pages WHERE page_id='"
                                  .$PageName['page_id']."' LIMIT 1 ");
      if(mysql_num_rows($investigate_id) == 0) {
        echo $PageName['page_id'].$PageName['name'];
      }
  }

我的问题是,我是否可以以某种方式避免大量的DB调用,因为它会对我管理的每个页面进行查询。我怎样才能做到这一点?

<?php
$IDs = array();
foreach($PageNames['data'] as $PageName){
    $IDs[] = $PageName['page_id'];
}
$investigate_id = mysql_query('SELECT page_id FROM pages WHERE page_id IN ('''.implode(''', ''', $IDs)).' LIMIT 1 ');
while($assoc = mysql_fetch_assoc($investigate_id)){
    // iff
}
?>

使用WHERE col IN将使一个查询将所有ID如此

WHERE page_id IN(1,3,45,6,6,7,5,2,1,5,76),它将在查询中执行,只需在结果上进行循环,然后为所欲为!

您可以从使用FQL获得的结果中收集ID,然后查询数据库中存在于结果中的行,以从结果中筛选数据库中存在的行。。。

$fql = <<<FQL
SELECT name, page_id FROM page WHERE page_id IN (
  SELECT page_id FROM page_admin  WHERE uid = me()
)
FQL;
// Get results from API
$pages = $facebook->api('/fql', array('q' => $fql));
// Collect pages for later usage by ID
$pagesByIds = array();
foreach($pages['data'] as $page){
    $pagesByIds[$page['page_id']] = $page;
}
// Query DB for all pages that exists in results
$pagesIds = implode(',', array_keys($pageByIds));
$res = mysql_query("SELECT page_id FROM pages WHERE page_id IN ({$pageIds})");
while($pageRow = mysql_fetch_assoc($res)){
  $pageId = $pageRow['page_id'];
  // Remove pages that present in API results and DB
  if (isset($pagesById[$pageId])) unset($pagesById[$pageId]); ;
}
// Display details for pages not existing in DB
foreach ($pagesByIds as $page){
  echo "ID: {$page['page_id']}, Name: {$page['name']} 'n"
}