Skip to main content

Explain Snap Shot StandBy database and the use of it

Explain Snap Shot StandBy database and the use of it?

Able to open standby database in read-write. This is very useful to turn our standby database into application testing / development purposes. This is achieved through snapshot standby database.

In order to create snapshot standby database:

1. Standby database must be a physical standby database
2. Flashback logging must be enabled on both primary and standby database
3. After enabling flashback mode, connect to dgmgrl utility in the primary database:
4. DGMGRL> CONVERT DATABASE STDBY TO SNAPSHOT STANDBY;
SQL> alter database convert to snapshot standby;

NOTE: Snap Shot StandBy – Is recommended if we have more than one standby database to the primary database.
From now on, we can do any testing (like creating new schemas, tables and so on) on our standby database. Please note that at this point of time; all the redo generated in our production database will be still shipped to standby database. 
But it is just that not going to be applied until the database is converted into physical standby mode.

5. Once the testing done, you can convert the snapshot standby database to physical standby with just 1 command:
DGMGRL>CONVERT DATABASE STDBY TO  PHYSICAL STANDBY;
6. Note that when the above command executed
All the changed made to the snapshot standby database (such as creating new schemas, tables) has been terminated
Previous physical standby database state is initiated
Physical standby database is mounted and MRP process is initiated. MRP will apply all the logs which was shipped yet applied during the snapshot standby database state.
7. Duration for this process is depends on few factors:
The amount of changes made to the database during the snapshot standby database state. More changes will lead to more time to rewind the changes via flashback database option.
The amount of archived logs generated during the snapshot standby database state. More archive logs will cause more time to apply it when the database is converted to physical standby database.
Labels:

Comments

Post a Comment

Popular posts from this blog

Issues and Solutions for Oracle 19c Grid Infrastructure Installation

     Common Issues and Solutions for Oracle 19c Grid Infrastructure Installation •       Check Log Files for Details Oracle installation issues often provide valuable clues in the log files. If the installer seems stuck or fails, check the following logs: ▪ Install log : /u01/app/oraInventory/logs/installActions<date>.log •       ▪ Grid Infrastructure log : $ORACLE_BASE/cfgtoollogs/ •         •       These logs can provide error messages and help identify the exact issue. •         •        Check Permissions and Ownership Verify that the Oracle Grid Infrastructure installation directories have the correct ownership and permissions. •        For example: •        Make sure the grid user has permission to write to the directories where the i...
Post a Comment
Read more

How to Improve Oracle Data Pump Performance - IMPDP

  How to Improve Oracle Data Pump Performance:- Use Parallelism : Set the PARALLEL parameter to at least 2 * number of CPUs . This allows multiple worker processes to perform tasks simultaneously, speeding up both export and import processes. Example: PARALLEL=4 for a system with 2 CPUs. Perform Import Using NETWORK_LINK : Use the NETWORK_LINK parameter to import data directly from the source database. This method is particularly helpful when space is constrained, as it streams the data without needing to generate dump files on the source. It can also reduce time compared to exporting and then importing, as data is streamed directly from the source to the target database. Disable Archivelog Mode (Standalone Databases) : For standalone databases, temporarily disable archive logging during the import process. Import operations can generate a lot of redo logs, slowing down the import. Disabling...
Post a Comment
Read more

Difference between AWR, ADDM and ASH reports

AWR: Automatic Workload Repository gathers, processes and maintains performance stats used for problem detection and self-tuning the databases. Different Components that uses AWR are: Automatic Database Diagnostic Monitor Undo Advisor SQL Tuning Advisor Segment Advisor Different types of AWR Reports for different purposes: For Single Instance Environment: @$ORACLE_HOME/rdbms/admin/awrrpt.sql For Oracle RAC Environment : @$ORACLE_HOME/rdbms/admin/awrgrpt.sql For a particular SQL Statement : @$ORACLE_HOME/rdbms/admin/awrsqrpt.sql For Comparing the reports : @$ORACLE_HOME/rdbms/admin/awrddrpt.sql ADDM: Automatic Database Diagnostic Monitoring Report analyzes the AWR data on a regular basis, to give you overview of the root cause of the problem which is affecting your database’s performance. It also provides suggestions or recommendations for rectifying any problem identified and lists the areas which are having no issues. ADDM recommends multiple solutions for the DBA to choose from which...
Post a Comment
Read more