DBMS_ALERT_INFO describes registered alerts.
| Column | Datatype | NULL | Description | 
|---|---|---|---|
| NAME | VARCHAR2(30) | NOT NULL | Name of the alert | 
| SID | VARCHAR2(30) | NOT NULL | Session ID of a session waiting for this alert | 
| CHANGED | VARCHAR2(1) | Boolean flag to indicate that an alert has been signaled. Y: alert signaled,N: no alert. | |
| MESSAGE | VARCHAR2(1800) | Optional message passed by signaler |