Table::get() will immediately evaluate the query and return an entity, or throw an exception if the record with the given primary key doesn't exist, ie it doesn't return a query, you cannot call isEmpty() on the result.
If you are using Table::get() you can catch the RecordNotFoundException:
try {
$user = $this->Users->get($uid);
// ...
} catch (\Cake\Datasource\Exception\RecordNotFoundException $exeption) {
// record doesn't exist
}
If you wanted to use isEmpty(), you'd need to use a regular query:
$query = $this->Users->findById($uid);
if ($query->isEmpty()) {
// record doesn't exist
}
If you don't actually need the result, you can use Table::exists():
$exists = $this->Users->exists(['id' => $uid]);
if ($exists !== true) {
// record doesn't exist
}
or a COUNT query:
$count = $this->Users->findById($uid)->count();
if ($count !== 1) {
// record doesn't exist
}
See also