private static function getNullables(string $table): array
    {
        if (self::$nullablesCache !== null && array_key_exists($table, self::$nullablesCache))
            return self::$nullablesCache[$table];

        // Ensure the database is connected!
        $pdo = Database::connect();

        /** @noinspection SqlResolve */
        $query = "
            SELECT
                column_name, data_type, is_nullable, column_default
            FROM 
                information_schema.columns
            WHERE table_name = '$table' AND is_nullable = 'YES' 
        ";

        self::$nullablesCache[$table] = [];

        $rows = $pdo->query($query);
        while($row = $rows->fetch())
            self::$nullablesCache[$table][$row["column_name"]] = $row;

        return self::$nullablesCache[$table];
    }