Question

我试图在游标迭代中获取一些结果，所以我得到了相关的元素和东西。但是当在迭代内部执行此查询时，即使还有更多数据需要，迭代游标也会终止并且迭代将结束。

一个例子

protected $em;
public function __construct() {
    $this->em = $this->get('doctrine')->getManager('default');
}
public function getProducts() {
    $query = "SELECT * FROM products"; // 100 Products
    $stmt = $this->select($query);

    while($result = $stmt->fetch()) {
        // This breaks the cursor so only 1 product is parsed.
        // If I remove this line, iteration ends perfectly (100 products)
        $pictures = $this->getPictures($result['id']);
    }
}
public function getPictures($product) {
    $query = "SELECT * FROM pictures WHERE product_id = :product_id";
    $stmt = $this->select($query, array('product_id' => $product));
    return $stmt->fetchAll();
}
public function select($query, array $params = array()) {
    $conn = $this->em->getConnection();
    $stmt = $conn->prepare($query);
    foreach($params as $key => $value) {
        $stmt->bindValue($key, $value);
    }
    $stmt->execute();

    return $stmt;
}

Answer 1

我认为你不能在不关闭前一个游标的情况下使用另一个游标。如果您查看ResullStatement接口：

/**
 * Closes the cursor, enabling the statement to be executed again.
 *
 * @return boolean TRUE on success or FALSE on failure.
 */
public function closeCursor();

当游标关闭时，通常会释放stmt内存。那么，为什么不为此只写一个查询呢？您可以使用子查询来提取所有产品ID。类似的东西：

从图片p中选择*，其中p.id IN（从产品pr中选择pr.id）`

Doctrine2在另一个迭代中断循环中创建新查询

1 个答案: