When a new trace is created, it is defined with a set of default event classes. You can remove these event classes and/or add others when you create new traces. Each time a new trace is created, the default event classes will be present unless explicitly removed.
These are the default event classes to trace.
| Default event class | Description |
|---|---|
| Connect | Connection event has occurred, such as a client requesting a connection to a server running Microsoft® SQL Server™. These are grouped within the Session event category. |
| Disconnect | Disconnect event has occurred, such as a client issuing a disconnect command. These are grouped within the Session event category. |
| ExistingConnection | Activity by all users that were logged on before the trace started has been detected. These are grouped within the Session event category. |
| RPC:Completed | RPC has completed. This is grouped within the TSQL event category. |
| SQL:BatchCompleted | Transact-SQL batch has completed. This is grouped within the TSQL event category. |