Berkeley DB: DbLog.archive
Полезная информация

DbLog.archive


import com.sleepycat.db.*;

public String[] archive(int flags) throws DbException;

Description

The DbLog.archive method returns an array of log or database file names.

By default, DbLog.archive returns the names of all of the log files that are no longer in use (e.g., no longer involved in active transactions), and that may safely be archived for catastrophic recovery and then removed from the system. If there were no file names to return, list will be set to null.

The flags argument is specified by logically OR'ing together one or more of the following values:

Db.DB_ARCH_ABS
All pathnames are returned as absolute pathnames, instead of relative to the database home directory.

Db.DB_ARCH_DATA
Return the database files that need to be archived in order to recover the database from catastrophic failure. If any of the database files have not been accessed during the lifetime of the current log files, DbLog.archive will not include them in this list. It is also possible that some of the files referenced in the log have since been deleted from the system.

Db.DB_ARCH_LOG
Return all the log file names regardless of whether or not they are in use.

The Db.DB_ARCH_DATA and Db.DB_ARCH_LOG flags are mutually exclusive.

See the db_archive manual page for more information on database archival procedures.

The DbLog.archive method is the underlying method used by the db_archive utility. See the db_archive utility source code for an example of using DbLog.archive in a POSIX 1003.1 environment.

The DbLog.archive method throws an exception that encapsulates an errno on failure.

Bugs

In a threaded application (i.e., one where the environment was created with the DB_THREAD flag specified), calling DbLog.archive will fail, returning EINVAL. To work around this problem, re-open the log explicitly without specifying DB_THREAD. This restriction is expected to be removed in a future version of Berkeley DB.

Errors

If a fatal error occurs in Berkeley DB, the DbLog.archive method may fail and throw a DbRunRecoveryException, at which point all subsequent database calls will also fail in the same way.

The DbLog.archive method may fail and throw an exception for any of the errors specified for the following Berkeley DB and C library functions: close(3), fcntl(3), fflush(3), fprintf(3), free(3), getcwd(3), getenv(3), getpid(3), getuid(3), isdigit(3), DbLog.compare, DbLog.get, malloc(3), memcpy(3), memset(3), open(3), qsort(3), realloc(3), sigfillset(3), sigprocmask(3), snprintf(3), stat(3), strchr(3), strcmp(3), strerror(3), strlen(3), unlink(3), vfprintf(3), and vsnprintf(3).

In addition, the DbLog.archive method may fail and throw an exception encapsulating errno for the following conditions:

EINVAL
An invalid flag value or parameter was specified.

The log was corrupted.

Class

DbLog

See Also

DbLog.archive, DbLog.close, DbLog.compare, DbLog.file, DbLog.flush, DbLog.get, DbLog.open, DbLog.put, DbLog.db_register, DbLog.stat, DbLog.unlink and DbLog.db_unregister.