Дмитрий Ким

select a.* from posts a
inner join (
select *, count (*) as cnt from post_author
where author_id in (1,2,3)
group by podt_id
having cnt = 3
) b on a.id = b.post_id

public function getFriendsList(){
  return $this->hasMany(UserRelation::className(),['user_id'=>'id'])->where(['or', ['user_id' => $this->id],['invite_id'=>$this->id]);
}

public function getFriendsList(){
  return UserRelation::find()->where(['or', ['user_id' => $this->id],['invite_id'=>$this->id]);
}

$values = [1, 2, 3];
$in_query = implode(',', array_fill(0, count($values), '?'));
$query = $DB->prepare(sprintf("UPDATE `Ttopic` SET `main`= ?, `main_id`= ?, `type`='".$f['type']."' WHERE `id` IN (%s) LIMIT 10", $in_query));
if($query->execute(array_merge([$main, $theme], $values)) echo 'ok';

INSERT INTO `tbl` (`col1`,`col2`...`colN`) SELECT `col1`,`col2`,...`colN` FROM `tbl` WHERE `code` = 123