QueryBuilder lastInsertId() - typo3

Question

I would like to have the last UID of the entry. For mysql, it is "insertId()". How does that work at Extbase?
$queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)->getQueryBuilderForTable($table);
$queryBuilder
->insert($table)
->values([
'test_id' => 1,
'test2_id' => 2,
]);
$queryBuilder->execute();
$queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)->getQueryBuilderForTable($table2);
$queryBuilder
->insert($table2)
->values([
'uid_local' => ?, // uid from $table
'uid_foreign' => 1
]);
$queryBuilder->execute();

Answer 1

You can get the last insert id with $queryBuilder->getConnection()->lastInsertId();
So that would make it:
$queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)->getQueryBuilderForTable($table);
$queryBuilder
->insert($table)
->values([
'test_id' => 1,
'test2_id' => 2,
]);
$queryBuilder->execute();
$tableUid = $queryBuilder->getConnection()->lastInsertId();
$queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)->getQueryBuilderForTable($table2);
$queryBuilder
->insert($table2)
->values([
'uid_local' => $tableUid,
'uid_foreign' => 1
]);
$queryBuilder->execute();

Answer 2

I'm a bit unsure if it's available when using the QueryBuilder for inserting new records, but the migration guide in TYPO3 Docs explain how you migrate the sql_insert_id() method in the new Doctrine Database Layer
https://docs.typo3.org/typo3cms/CoreApiReference/ApiOverview/Database/Migration/Index.html#sql-insert-id
Hint:
(int)$databaseConnectionForPages->lastInsertId('pages');