standby physical couldnot query v$database

all,

I have a physical standby database, but a little error comes when open read only and again MRP apply.

startup nomount;
alter database mount standby database;
alter database managed standby database disconnect from session; select open_mode from v$database;
-- yield mount

alter database managed standby database cancel; alter database open read only;
select open_mode from v$database;
-- yield read only

• back activate MRP alter database managed standby database disconnect from session; select open_mode from v$database;
• yield error, that v$database could not query
• but i can still query other v$ views, such as v$instance, v$datafile , etc

--

regards
ujang

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