计算另一个连接表中的行数

Question

我创建了两个表。 一个episode表和一个season表，我想知道我如何 select 并显示每个季节的剧集计数或将它们保存在season.episodes_count什么是正确的方法或查询这样做？

try {
    $stmt = $db->prepare("SELECT * FROM `season` WHERE season.show_id = '" . $show_id . "' ORDER BY season_number DESC");
    // how to select episodes_count?
    $stmt->execute();
    $seasons = $stmt->fetchAll(PDO::FETCH_ASSOC);
} catch (PDOException $e) {
    echo $e;
}

Answer 1

嗨，没有要测试的数据库，这没有经过测试，但是像这样：

    $stmt = $db->prepare("
    SELECT se.id,
    se.season_number,
    COUNT(es.id) AS episodes_count
    FROM season AS se
    LEFT JOIN espisode AS es ON (se.id = es.season_id)
    WHERE se.show_id = $show_id
    ORDER BY se.season_number DESC
    ");