当运行下面的DQL时,从原则2中仅选择区分列时,我需要一些帮助
SELECT p.type FROM AppBundle\Entity\Product p
type
是实体AppBundle\Entity\Product
中的鉴别符列@ORM\DiscriminatorColumn(name="type", type="smallint")`
@ORM\DiscriminatorMap({
"0" = "AppBundle\Entity\Product",
"1" = "AppBundle\Entity\Product\SingleIssue",
"2" = "AppBundle\Entity\Product\CountBasedIssue",
"3" = "AppBundle\Entity\Product\TimeBasedIssue"
})
我知道
type
在实体中不是不动产,但是我仍然可以这样做吗?提前致谢!
更新
在阅读了两天的代码后,我决定重写SqlWalker并通过下面的代码片段创建新的Hydrator
覆盖SqlWalker
<?php
namespace ...;
use Doctrine\ORM\Query\SqlWalker;
class CustomSqlWalker extends SqlWalker
{
const FORCE_GET_DISCRIMINATOR_COLUMN = 'forceGetDiscriminatorColumn';
const DISCRIMINATOR_CLASS_MAP = 'discriminatorClassMap';
/**
* {@inheritdoc}
*/
public function walkSelectClause($selectClause)
{
$sql = parent::walkSelectClause($selectClause);
$forceGetDiscriminatorColumn = $this->getQuery()->getHint(self::FORCE_GET_DISCRIMINATOR_COLUMN);
if (empty($forceGetDiscriminatorColumn)) {
return $sql;
}
foreach ($this->getQueryComponents() as $key => $queryComponent) {
if (!in_array($key, $forceGetDiscriminatorColumn)) {
continue;
}
$metadata = $queryComponent['metadata'];
$discriminatorColumn = $metadata->discriminatorColumn['name'];
$tableName = $metadata->table['name'];
$tableAlias = $this->getSQLTableAlias($tableName, $key);
$discriminatorColumnAlias = $this->getSQLColumnAlias($discriminatorColumn);
$sql .= ", $tableAlias.$discriminatorColumn AS $discriminatorColumnAlias";
}
return $sql;
}
}
定制水合器
<?php
namespace ...;
use Doctrine\ORM\Internal\Hydration\ArrayHydrator;
use PDO;
class CustomHydrator extends ArrayHydrator
{
/**
* {@inheritdoc}
*/
protected function hydrateAllData()
{
$result = array();
$rootClassName = null;
if (isset($this->_hints['forceGetDiscriminatorColumn']) &&
isset($this->_hints['discriminatorClassMap'])) {
$rootClassName = $this->_hints['discriminatorClassMap'];
}
while ($data = $this->_stmt->fetch(PDO::FETCH_ASSOC)) {
foreach ($data as $key => $value) {
if ($this->hydrateColumnInfo($key) != null ||
empty($rootClassName)) {
continue;
}
$metadata = $this->getClassMetadata($rootClassName);
$discriminatorColumn = $metadata->discriminatorColumn;
$fieldName = $discriminatorColumn['fieldName'];
$type = $discriminatorColumn['type'];
$this->_rsm->addScalarResult(
$key, $fieldName, $type
);
}
$this->hydrateRowData($data, $result);
}
return $result;
}
}
配置自定义水化器
orm:
...
hydrators:
CustomHydrator: YourNamespace\To\CustomHydrator
最后一步
$query = $queryBuilder->getQuery();
$query->setHint(\Doctrine\ORM\Query::HINT_CUSTOM_OUTPUT_WALKER, 'YourNamespace\To\CustomSqlWalker');
$query->setHint(\YourNamespace\To\CustomSqlWalker::FORCE_GET_DISCRIMINATOR_COLUMN, array($rootAlias)); // this alias will be used in CustomSqlWalker class
$query->setHint(\YourNamespace\To\CustomSqlWalker::DISCRIMINATOR_CLASS_MAP, $this->getClassName()); // this full-qualify class name will be used in CustomHydrator class
$products = $query->getResult('CustomHydrator');
TL; DR
我知道这是一个非常复杂的解决方案(可能只是针对我的情况),所以我希望有人可以给我另一种简单的方法来解决此问题,非常感谢!
最佳答案
没有直接访问“鉴别符”列的权限。
您可以使用INSTANCE OF
DQL as described in the docs查询实体的类型。例如:
$query = $em->createQuery("SELECT product FROM AppBundle\Entity\AbstractProduct product WHERE product INSTANCE OF AppBundle\Entity\Product");
$products = $query->getResult();
希望这可以帮助
关于php - 如何在准则2中选择区分列,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/33360211/