/*
*
*  Author     : Vishal Gupta
*  Purpose    : Remove extra online redolog members.
*  Version    : 
*  Parameters : None
*               
*
*  Revision History:
*  ===================
*  Date       Author        Description
*  ---------  ------------  -----------------------------------------
*  17-DEC-15  Vishal Gupta  Created
*
*
*/

set serveroutput on
BEGIN
    -- Remove extra redo log member from non-current online redologs
    FOR i in 
    (SELECT 'alter database drop logfile member ''' 
          || max(lf.member) 
          || '''' sqltext
      , l.status
      FROM v$log l
           JOIN v$logfile lf ON lf.group# = l.group#
    WHERE l.members = 2
      and l.status NOT IN ('CURRENT')
    group by l.group#, l.status
    ORDER BY l.group#
    )
    LOOP
       dbms_output.put_line(i.sqltext || ';');
     execute immediate i.sqltext;
    END LOOP;
    
    -- Switch current online redo and remove extra member
    FOR i in 
    (SELECT 'alter database drop logfile member ''' 
          || max(lf.member) 
          || '''' sqltext
      , 'alter system archive log instance ''' || i.instance_name || ''' current' sqltext2  
          , l.status
      FROM v$log l
           JOIN v$logfile lf ON lf.group# = l.group#
       JOIN gv$instance i ON i.inst_id = l.thread#
    WHERE l.members = 2
      and l.status = 'CURRENT'
    group by l.group#, i.instance_name, l.status
    ORDER BY l.group#, i.instance_name
    )
    LOOP
       dbms_output.put_line(i.sqltext2 || ';');
     execute immediate i.sqltext2;
       dbms_output.put_line(i.sqltext || ';');
     execute immediate i.sqltext;
    END LOOP;
END;
/