2.5.1 Verifying That True Cache Is Working as Expected

To verify that True Cache is applying redo and making progress, check the following queries on True Cache.

1. Run SQL*Plus on the True Cache.

   sqlplus / as SYSDBA

2. Enter the following query:

   SELECT database_role, open_mode FROM v$database;

   The output should look like this:

   DATABASE_ROLE    OPEN_MODE
   ---------------- --------------------
   TRUE CACHE       READ ONLY WITH APPLY

   If OPEN_MODE is READ ONLY WITH APPLY, it means that the True Cache redo apply is actively working.

3. Enter the following query multiple times:

   SELECT current_scn FROM v$database;

   If CURRENT_SCN is advancing over time, it means that True Cache is moving forward as expected.

4. To find the size of each log file, enter the following query:

   SELECT THREAD#, SEQUENCE#, BYTES FROM v$standby_log;