How to do Subquery for same Table in Yii2 Eloquent - yii

Question

how to create this query using model in yii2
select *,p1.plan_id from product p1
where id in (select max(p2.id) from product p2 where p2.plan_id = p1.plan_id)
form the following table Product
id product_name plan_id
-------------------------------
1 bottle 1
2 book 2
3 book 2
4 bottle 1
5 notbook 3

Answer 1

You could refactor you query using an inner join eg:
$sql = "select *
from product p1
inner join (
select plan_id, max(id) max_id
from product
group by plain_id
) t on t.plan_id = p1.plan_id and p1.id = t.max_id";
and in some case could be useful findBySql, assuming your model is name Product
$models = Product::findBySql($sql)->all();

Answer 2

This should be the exact query you would do, but it won't work for MySQL:
// select *, p1.plan_id from product p1
// where id in (select max(p2.id) from product p2 where p2.plan_id = p1.plan_id)
$subquery = (new \yii\db\Query)->select('[[p2]].[[id]]')
->from(['p2' => 'product'])
->where('[[p2]].[[plan_id]] = [[p1]].[[plan_id]]')
->orderBy('[[p2]].[[id]] DESC')->limit(1); // equiv to max(p2.id)
$query = (new \yii\db\Query)->from(['p1' => 'product'])
->where(['p1.id' => $subquery])
->one();
// PS: Yii will quote fields wrapped in `[[]]` double square-brackets.
Using joins
So, you should use innerJoin (or other variants) to achieve the same result working for any database:
$query = (new \yii\db\Query)->from(['p1' => 'product'])
->innerJoin(['product p2'], '[[p2]].[[plan_id]] = [[p1]].[[plan_id]]')
->orderBy('[[p2]].[[id]] DESC')->limit(1); // equiv to max(p2.id)
->one();