数据字典视图之：DBA_LOGSTDBY_LOG结构

DBA_LOGSTDBY_LOG是逻辑Standby数据库中比较重要的一个字典视图，该视图用来记录当前的归档日志应用情况，通过该视图可以查看应用日志的SEQUENCE#,APPLIED状况等。

该视图的构建语法如下（来自Oracle 11gR1数据库）：

SELECT thread#, resetlogs_change#, reset_timestamp resetlogs_id, sequence#,
       first_change#, next_change#, first_time, next_time, file_name,
       TIMESTAMP, dict_begin, dict_end,
       (CASE
           WHEN l.next_change# < p.read_scn
              THEN 'YES'
           WHEN ((BITAND (l.CONTENTS, 16) = 16) AND (BITAND (l.status, 4) = 0))
              THEN 'FETCHING'
           WHEN ((BITAND (l.CONTENTS, 16) = 16) AND (BITAND (l.status, 4) = 4))
              THEN 'CORRUPT'
           WHEN l.first_change# < p.applied_scn
              THEN 'CURRENT'
           ELSE 'NO'
        END
       ) applied
  FROM SYSTEM.logmnr_log$ l, dba_logstdby_progress p
 WHERE session# = (SELECT VALUE
                     FROM SYSTEM.logstdby$parameters
                    WHERE NAME = 'LMNR_SID')
   AND (flags IS NULL OR BITAND (l.flags, 16) = 0);

引用Oracle文档说明如下：

DBA_LOGSTDBY_LOG displays information about the logs registered for a logical standby database. This view is for logical standby databases only.