foreach如果声明php

Question

我有一个从mysql中的数据生成的目录。我希望在某些类别之后加入广告。我是否只需在ifach类别中添加if语句，以查看某个类别是否与我想要广告的类别相匹配？

try
    {
        $dbh = new PDO('mysql:host=localhost;dbname=YOURDB', 'USERNAME', 'PASSWORD');
    }
    catch(PDOException $e)
    {
        echo $e->getMessage();
        die;
    }

    $stmt = $dbh->query('SELECT category FROM businesses GROUP BY category');
    $stmt->setFetchMode(PDO::FETCH_ASSOC);

    $categories = $stmt->fetchAll();
    foreach ($categories as $category)
    {
        echo '<h3>'.$category['category'].'</h3>';

        $stmt = $dbh->prepare('SELECT * FROM businesses WHERE category = :categoryName');
        $stmt->bindParam(':categoryName', $category['category'], PDO::PARAM_STR);
        $stmt->execute();
        $businesses = $stmt->fetchAll();

        foreach ($businesses as $business)
        {
            echo $business['name'];
            echo '<br />';
        }
    }