<?php

use yii\db\Migration;

class m161115_112721_price extends Migration
{
    public function up()
    {
        $createTriggerSql = <<< SQL
            CREATE
                TRIGGER `min_price` AFTER UPDATE ON `tour`
                FOR EACH ROW BEGIN
            
                UPDATE entity e
                JOIN
                    ( SELECT t.entityId, MIN(t.price) AS price
                      FROM tour t
                      WHERE t.price > 0 AND t.entityId = NEW.entityId
                    ) nw
                ON nw.entityId = e.id
                SET e.price = nw.price
                WHERE e.id = NEW.entityId;
            END;
SQL;

        $this->execute('DROP TRIGGER /*!50032 IF EXISTS */ `min_price`');
        $this->execute($createTriggerSql);
    }

    public function down()
    {
        $this->execute('DROP TRIGGER /*!50032 IF EXISTS */ `min_price`');
    }

}