protected function getTableForeignKeys(): array
    {
        $data = [];

        $fks = $this->db->schema->getTableForeignKeys($this->tableName, true);

        /* @var $fk ForeignKeyConstraint */
        foreach ($fks as $fk) {
            $data[$fk->name] = new TableForeignKey([
                'name' => $fk->name,
                'columns' => $fk->columnNames,
                'refTable' => $fk->foreignTableName,
                'refColumns' => $fk->foreignColumnNames,
                'onDelete' => $fk->onDelete,
                'onUpdate' => $fk->onUpdate,
            ]);
        }

        return $data;
    }