What is logical standby database?

What is logical standby database?

A logical standby database works by copying your primary site with a backup. Then a process called SQL Apply takes the archive logs from the primary site and extracts the SQL statements from them to apply them to the logical standby database. During this time, the logical standby database is up and open.

How do I check standby database?

HOW TO QUERY DATAGUARD STATUS

1. SELECT DATABASE_ROLE, DB_UNIQUE_NAME INSTANCE, OPEN_MODE, PROTECTION_MODE, PROTECTION_LEVEL, SWITCHOVER_STATUS FROM V$DATABASE;
2. On the standby database, query the V$ARCHIVED_LOG view to verify the archived redo log files were applied.

How do you rebuild a logical standby database?

1. Create a Backup Copy of the Primary Database Datafiles.
2. Create a Control File for the Standby Database.
3. Create a Parameter File for the Standby Database.
4. Copy Files from the Primary System to the Standby System.
5. Set Up the Environment to Support the Standby Database.
6. Start the Physical Standby Database.

What is physical and logical standby database?

Physical standby databases are physically identical to primary databases, meaning all objects in the primary database are the same as in standby database. Logical Standby Databases are logically identical to primary databases although the physical organization and structure of the data can be different.

What is the use of logical standby database?

Logical standby databases Following are a few of the primary benefits for a logical standby: Allow near zero downtime for database upgrades. Ability to offload reporting from the primary database. Ability to create additional objects to better support reporting operations.

How do I check standby logs?

1. Step 1 : Check the status of database on both server.
2. Step 2 : Check for GAP on Standby.
3. Step 3 & 4: Check redo received and applied on standby.
4. Step 5: Identify the missing archive log file.
5. Step 6: Copy missing archive log file.
6. Step 7: Register archive logfile with standby.

What is snapshot standby Oracle?

A snapshot standby database is a fully updateable standby database created by converting a physical standby database into a snapshot standby database. A snapshot standby database receives and archives, but does not apply, redo data from a primary database.

How do I stop logical standby database?

To stop SQL Apply, issue the following statement on the logical standby database: SQL> ALTER DATABASE STOP LOGICAL STANDBY APPLY; When you issue this statement, SQL Apply waits until it has committed all complete transactions that were in the process of being applied.

How do I check my primary standby database status?

When to enable or disable a logical standby database?

The ALTER SESSION [ENABLE|DISABLE] GUARD statement is useful when you want to temporarily disable the database guard to make changes to the database, as described in Modifying a Logical Standby Database . Do not let the primary and logical standby databases diverge while the database guard is disabled.

Is there a read and write capability for logical standby?

Logical standby introduced with read and write capability so that DDL, DML on Logical standby and also recovery will be in progress from primary database. You must know that logical standby and primary databases Logical standby is no more considered as mirror to the primary database.

Why does SQL apply reevaluate SYSDATE at logical standby?

Because SQL Apply reissues the same DDL at the logical standby, the function sysdate () is reevaluated at the logical standby. Thus, the column start_date is created with a different default value than at the primary database. The DDL fires DML triggers defined on the target table.

How to create a password in a logical standby database?

You must create the password verification function manually at the logical standby database, and associate it with the appropriate profiles. The SQL ALTER DATABASE GUARD statement controls user access to tables in a logical standby database. The database guard is set to ALL by default on a logical standby database.