Symfony 原则SQL查询顺序按ASC NULL Last

我使用原则2.4。我尝试按优先级升序排列活动列表，优先级为NULL，最后优先级为0

SELECT * FROM campaign ORDER BY priority IS NULL, priority = 0, priority ASC

你知道我怎么做吗

$query->addOrderBy('c.priority', 'ASC');

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我找到了解决方案，我做到了：

$query->addSelect('CASE WHEN c.priority IS NULL THEN 1 ELSE 0 END as HIDDEN priority_is_null');
$query->addSelect('CASE WHEN c.priority = 0 THEN 1 ELSE 0 END as HIDDEN priority_is_zero');
$query->addOrderBy('priority_is_null', 'ASC');
$query->addOrderBy('priority_is_zero', 'ASC');
$query->addOrderBy('c.priority', 'ASC');

$query->addSelect('CASE WHEN c.priority IS NULL THEN 1 ELSE 0 END as HIDDEN priority_is_null');
$query->addSelect('CASE WHEN c.priority = 0 THEN 1 ELSE 0 END as HIDDEN priority_is_zero');
$query->addOrderBy('priority_is_null', 'ASC');
$query->addOrderBy('priority_is_zero', 'ASC');
$query->addOrderBy('c.priority', 'ASC');