Alert Log File
The alert log file keeps a record of the following information:
• When the database was started or shut down.
• A list of all non-default initialization parameters
• The startup of background processes
• The thread being used by the instance
• The log sequence number LGWR is writing to
• Information regarding a log switch
• Creation of tablespaces and undo segments
• Alter statements that have been issued
• Information regarding error messages such as ORA-600 and extent errors.