Compare for existing values from 2 foreach loops?

I have 2 foreach loop's where i get new results from my first db and i have second foreach where i get data from second db

My first foreach code is:

foreach($_existing_data_result as $result) {
echo $result->name.'<br>';
}

second foreach:

foreach($_new_data_result as $resultNew) {
echo $resultNew->name.'<br>';
}

I need to check on second foreach if result exist in first then ignore this result, i tried it with in_array()but i always see double names...