def insert_all(db, schema_name, table_name, columns, items):
    """
    Insert all item in given items list into the specified table, schema_name.table_name.
    """
    table = '{0}.{1}'.format(schema_name, table_name) if schema_name else table_name
    columns_list = ', '.join(columns)
    values_list = ', '.join(['?'] * len(columns))
    query = 'INSERT INTO {table} ({columns}) VALUES ({values})'.format(
        table=table, columns=columns_list, values=values_list)
    for item in items:
        values = [getattr(item, col) for col in columns]
        db.execute(query, values)
Insert all item in given items list into the specified table, schema_name.table_name.