如果在Symfony- MongoDB-ODM中数据为空，则在odm查询（游标）上执行count（）不会返回“0”

问题描述：

Performing count() on odm query (cursor) does not return "0" if data is empty in Symfony- MongoDB-ODM

$query = $this->dm->createQueryBuilder('AppBundle:DocumentName');
$count = $query->getQuery()->count();

The var $count always returns value greater than zero ("0"). Even if there is no data in document

Note : Converting cursor to arrays consumes more memory, Please Excuse this method.

答

You should do:

$count = $query->getQuery()->getSingleScalarResult();

Regards

答

you can use AggregationBuilder. Try this code in your documentNameRepository:

$qb = $this->createAggregationBuilder('Document\DocumentName');
$qb->count('nb_documents');
$results = $qb->execute();
return $results;

You can execute where operation before the count like below:

$qb->match()
   ->field('field_name')
   ->equals(10);

You can execute limit and skip operation before the count like below:

$qb->skip(10)
   ->limit(100);