An asynchronous mapping to DB-API 2.0.
| Class | ConnectionLost | This exception means that a db connection has been lost. Client code may try again. |
| Class | Connection | A wrapper for a DB-API connection instance. |
| Class | Transaction | A lightweight wrapper for a DB-API 'cursor' object. |
| Class | ConnectionPool | Represent a pool of connections to a DB-API 2.0 compliant database. |