/**
* @throws \yii\db\Exception
*/
private function generateLinks()
{
$c = Yii::$app->db->createCommand();
$newBatch = [];
$currentTeacherId = $this->minTeacherId;
do {
$studentsNum = rand(0, $this->getConfig('max_teacher_students'));
if (0 == $studentsNum) {
continue;
}
$batch = [];
while (count($batch) < $studentsNum) {
$batch[rand($this->minStudentId, $this->maxStudentId)] = true;
}
foreach ($batch as $k => $_) {
$newBatch[] = [$k, $currentTeacherId];
}
if (count($newBatch) >= $this->getConfig('insert_portion_size')) {
$c->batchInsert(StudentTeacher::tableName(), ['student_id', 'teacher_id'], $newBatch);
$c->execute();
$newBatch = [];
}
$currentTeacherId++;
} while ($currentTeacherId <= $this->maxTeacherId);
if (!empty($newBatch)) {
$c->batchInsert(StudentTeacher::tableName(), ['student_id', 'teacher_id'], $newBatch);
$c->execute();
}
}
/**
* @return \yii\db\ActiveQuery
*/
public function getListWithStudentsCounrt()
{
$query = Teacher::find()->joinWith(StudentTeacher::tableName())->addSelect([Teacher::tableName() . '.*', 'COUNT(' . StudentTeacher::tableName() . '.student_id) as student_count'])->groupBy(Teacher::tableName() . '.id');
return $query;
}
