$filter['field'] = ['neq','not null']; //不为空
$filter['field'] = null; //null
或者
$filter[''] = [Db::raw('field IS NULL')]
$filter[''] = [Db::raw('field IS NOT NULL')]
转载自:https://blog.youkuaiyun.com/qazx123q/article/details/99408992
$filter['field'] = ['neq','not null']; //不为空
$filter['field'] = null; //null
或者
$filter[''] = [Db::raw('field IS NULL')]
$filter[''] = [Db::raw('field IS NOT NULL')]
转载自:https://blog.youkuaiyun.com/qazx123q/article/details/99408992