Why doesn't codeception see the temporary table?

Question

Yii

I'm testing a class for batch insertion into the database.
I create a temporary table for the test (in setUp or in the test method, it doesn't matter)

Yii::$app->db->createCommand(
      'CREATE TEMPORARY TABLE {{%table_loading}} SELECT * FROM {{%table}} LIMIT 0'
    )->execute();

After some operations, I check for the presence of:

$I->canSeeInDatabase('table_loading', ['brand_name'=>'brand_1', 'article_name'=>'article_1', 'no_in_part'=>1]);

As a result of this statement I get an error

Base table or view not found: 1146 Table 'mydatabase.table_loading' doesn't exist

To check in the same test, I added (new \yii\db\Query)->from('{{%table_loading}}')->count() - it works properly. As I understand it, codeception has one connection for the Db module, and Yii::$app->db has another connection, which is why the temporary table is not available.
If my guesses are correct, then the question is for the guru - how to test in such situations, what is good practice?

Answer 1

If we are talking about Yii2, Codeception for connecting the database inherits the Yii config, redefining only dsn (the name of the test base, see tests/codeception/config/config.php). In this case, the simplest thing is to stick a debugger after CREATE TEMPORARY TABLE and see where the table is being created.

Answer 2

Because the temporary table lives within one session of a DB. The tested script works with one session, codeception creates its own session, from which the first one is not visible. But what to do with it is not clear