php - Symfony2: is ArrayCollection better than multiple db queries? -

in symfony2 have 2 entities (companies , employees) one-to-many relation (one company can have multiple employees).
each employee object has id, company_id (foreign key), badge_number, last_updated datetime field, name, etc

easy, right?
comes tricky part...

each day (from api) $company_upd array contains list of companies updated of employees data. then, each company in $company_upd, retrieve api $company_employees_list array cointains new list of employees .

then loop through array identify new/updated record needs persisted in local database. this:

foreach ($company_employees_list $employee){      $local_employee = $repo->findoneby("badge_number" => $employee["badge_number"];      //if there employee record same badge_number      if($local_employee){          //compare last_updated field see if employee record needs updated          if($employee["badge_number"] > $local_employee->getlastupdated()){              //update record , persist database             $local_employee->setsomething($employee["some_value"];          }      } else {           //create new employee object , persist database          $new_employee = new employee();          $new_employee->setsomething('some_value');          $em->persist($new_employee);      }  }  $em->flush(); 

of course, approach works fine i'm doing query foreach employee foreach company!! (to retrieve corresponding object , update it)

is possible (and better) use arraycollection? mean: fetch employees arraycollection 1 time , then, work it. search if there employee record specific badge_number , update , persist database? so, basically, did in code above using array_collection instead of separate queries. if new approach faster/better.

if indeed possible (and faster), please write mockup code better understand how manipulate arraycollection , want?

//fetch local db employees arraycollection $employees_ar_coll = $company->getemployees();  //what now???? =) 

p.s. api works this, can't change that.