def mysql_large_prefix_check(engine):
    """Check mysql has innodb_large_prefix set"""
    if not str(engine.url).startswith('mysql'):
        return False
    with engine.begin() as connection:
        variables = dict(
            connection.execute(
                text(
                    'show variables where variable_name like '
                    '"innodb_large_prefix" or '
                    'variable_name like "innodb_file_format";'
                )
            ).fetchall()
        )
    if (
        variables.get('innodb_file_format', 'Barracuda') == 'Barracuda'
        and variables.get('innodb_large_prefix', 'ON') == 'ON'
    ):
        return True
    else:
        return False
Check mysql has innodb_large_prefix set
jupyterhub/orm.py