You should always monitor dataguard status if it is running or not syncronized or not.
You can read other Oracle Dataguard monitoring scripts like following.
Your dataguard is running but is there any lag ? You can learn below script.
set lines 1000 select name,value from v$dataguard_stats;
If you want to know which archive sequence number comes from the Primary database lastly and which is last applied in Standby, you can learn the following script.
SELECT ARCH.THREAD# "Thread", ARCH.SEQUENCE# "Last in Sequence", APPL.SEQUENCE# "Last Applied Sequence", (ARCH.SEQUENCE# - APPL.SEQUENCE#) "Difference" FROM (SELECT THREAD# ,SEQUENCE# FROM V$ARCHIVED_LOG WHERE (THREAD#,FIRST_TIME ) IN (SELECT THREAD#,MAX(FIRST_TIME) FROM V$ARCHIVED_LOG GROUP BY THREAD#)) ARCH, (SELECT THREAD# ,SEQUENCE# FROM V$LOG_HISTORY WHERE (THREAD#,FIRST_TIME ) IN (SELECT THREAD#,MAX(FIRST_TIME) FROM V$LOG_HISTORY GROUP BY THREAD#)) APPL WHERE ARCH.THREAD# = APPL.THREAD# ORDER BY 1;
What is the MRP process waiting for status ? You can check with below script.
select a.event, a.wait_time, a.seconds_in_wait from gv$session_wait a, gv$session b where a.sid=b.sid and b.sid=(select SID from v$session where PADDR=(select PADDR from v$bgprocess where NAME='MRP0'));
Do you want to learn Oracle Database for Beginners, then read the following articles.
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