Showing posts from August, 2016

Step by Step - How to resolve redo log file corruption using ALTER DATABASE CLEAR UNARCHIVED LOGFILE command

Connect to sys using sqlplus in admin command prompt Check whether your database is in archive log mode or not. Run command ARCHIVE LOG LIST. It will show you the following details: It is always preferable to have your database in archive log mode. The reason being if your database is in archive log mode you can recover from all committed changes in the event of an OS or disk failure. This query will display the path of redo log files, their group and their status. It is always recommended to have a minimum of two members in one group. As you can see I have only 1 member in group 6 whose current status is INACTIVE. I intentionally have 1 member to generate a scenario for the sake of this practical. Now go to the specified path where the redo log member of group 6 is located and open it in a notepad. It will show some symbolic data. Delete couple of lines and save it the original location which is the one we got as a result of query. Why did we do the above step i.