How conversion mysql query into yii2 - yii2

Question

Select tickets.id with calendar_date is null if last tickets.p_id(child row) calendar_date is null.
I want to convert this query in yii2 search model:
mysql query:
`SELECT b.ticket_id FROM (SELECT a.ticket_id FROM (
SELECT t.id AS ticket_id FROM tech_support.tickets t
WHERE t.tree_status_id = 2 AND t.p_id IS NULL) a
LEFT JOIN tech_support.tickets tt ON tt.p_id = a.ticket_id
WHERE tt.p_id IS NULL) b
LEFT JOIN tech_support.tickets ttt ON ttt.id = b.ticket_id WHERE
ttt.calendar_date IS NULL UNION ALL
SELECT b.maxid FROM (SELECT a.maxid, tt.calendar_date FROM (
SELECT MAX(t.id) AS maxid FROM tech_support.tickets t WHERE
t.tree_status_id = 2 GROUP BY t.p_id) a
LEFT JOIN tech_support.tickets tt ON tt.id = a.maxid) b
WHERE b.calendar_date IS NULL;`
yii2 code:
$subQuery = Tickets::find()
->select(new Expression('id as ticket_id'))
->where('tree_status_id = 2')
->andWhere('p_id is null')
->alias('a');
$subQuery->leftJoin('tickets', 'tickets.p_id = a.ticket_id')
->where('tickets.p_id is null')->all();
$query1 = (new \yii\db\Query())
->select(new Expression('id as ticket_id'))
->from($subQuery)
->where('p_id is null')
->alias('b');
$query1->leftJoin(['ttt' => 'tickets'], 'ttt.id =
b.ticket_id')
->where('ttt.calendar_date IS NULL');
$subQuery2 = Tickets::find()
->select(new Expression('MAX(tickets.id) as maxid'))
->where('tree_status_id = 2')
->groupBy(['p_id'])
->alias('a');
$subQuery2->leftJoin(['tt' => 'tickets'], 'tt.id = a.maxid')
->all();
$query2 = (new \yii\db\Query())
->select('maxid')
->from($subQuery2);
$query1->union($query2);
$query1->where('calendar_date is null');
Error Info:
Integrity constraint violation – yii\db\IntegrityException
Please help me.

Answer 1

Result:
//----------------query1------------------------------
$query = (new \yii\db\Query())
->select('t.id as ticket_id')
->from(['t' => 'tickets'])
->where('t.tree_status_id = 2')
->andWhere('t.p_id is null');
$subQuery = (new \yii\db\Query())
->select('a.ticket_id')
->from(['a' => $query]);
$subQuery->leftJoin(['tt' => 'tickets'], 'tt.p_id = a.ticket_id')
->where('tt.p_id is null');
$query1 = (new \yii\db\Query())
->select('b.ticket_id')
->from(['b' => $subQuery]);
$query1->leftJoin(['ttt' => 'tickets'], 'ttt.id = b.ticket_id')
->where('ttt.calendar_date IS NULL');
//----------------query2------------------------------
$subQuery2 = (new \yii\db\Query())
->select('MAX(t.id) as maxid')
->from(['t' => 'tickets'])
->where('t.tree_status_id = 2')
->groupBy(['t.p_id']);
$query2 = (new \yii\db\Query())
->select(['a.maxid', 'tt.calendar_date'])
->from(['a' => $subQuery2]);
$query2->leftJoin(['tt' => 'tickets'], 'tt.id = a.maxid');
$query3 = (new \yii\db\Query())
->select('b.maxid')
->from(['b' => $query2]);
$query3->leftJoin(['ttt' => 'tickets'], 'ttt.id = b.maxid')
->where('ttt.calendar_date IS NULL');
//----------------union queries------------------------------
$unionQuery = (new \yii\db\Query())
->from([$query1->union($query3, true)]);