Alter system archive log current/all/switch logfile
Alter system switch logfile;
Force log switching is performed on the current instance in a single instance database or RAC to archive the current redo log. If automatic archiving is not enabled before Oracle9i, the current redo log file will not be archived.
Alter system archive log current;
Switch all instances in the database (only archive the current log ).
Alter system archive log all;
Archive non-archive logs in the database and do not archive current logs. There are 6 groups of logs in a busy system, namely group1 ~ 6. The current log group is group5, while the archiving process is operating on group3, which has not been written yet. At this time, group4 is an Unarchived non-current log.
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In Oracle9i and earlier versions, in ARCHIVELOG mode, when LOG_ARCHIVE_START = FALSE, when the system loops to the first group of Unarchived logs, the system will hang and must be manually archived by DBA, if the number of log groups is large, run alter system archive log all.
If LOG_ARCHIVE_START = TRUE, you only need to run: alter system archive log current;
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The log_archive_start parameter is discarded in 10 Gb --
In Oracle10g, The log_archive_start parameter has been deprecated. As long as the database archive mode is started, Oracle will enable automatic archiving to avoid some problems caused by user negligence before 10g.