Physical standby:
Physical standby schema matches exactly the source database. It is block-for-block identical copy of the primary database.
Archived redo logs and FTP'ed directly to the standby database which is always running in "recover" mode. Upon arrival, the archived redo logs are applied directly to the standby database.
It uses standard recovery techniques of an Oracle database to apply redo data.
Logical standby:
Logical standby database does not have to match the schema structure of the source database.
It uses SQL Apply engine, SQL Apply Engine transforms redo data received from the primary into logical SQL statements and then executes those SQL statements against the standby database.
Logical standby uses LogMiner techniques to transform the archived redo logs into native DML statements (insert, update, delete). This DML is transported and applied to the standby database.
Logical standby tables can be open for SQL queries (read only), and all other standby tables can be open for updates.
Logical standby database can have additional materialized views and indexes added for faster performance.
Physical standby schema matches exactly the source database. It is block-for-block identical copy of the primary database.
Archived redo logs and FTP'ed directly to the standby database which is always running in "recover" mode. Upon arrival, the archived redo logs are applied directly to the standby database.
It uses standard recovery techniques of an Oracle database to apply redo data.
Logical standby:
Logical standby database does not have to match the schema structure of the source database.
It uses SQL Apply engine, SQL Apply Engine transforms redo data received from the primary into logical SQL statements and then executes those SQL statements against the standby database.
Logical standby uses LogMiner techniques to transform the archived redo logs into native DML statements (insert, update, delete). This DML is transported and applied to the standby database.
Logical standby tables can be open for SQL queries (read only), and all other standby tables can be open for updates.
Logical standby database can have additional materialized views and indexes added for faster performance.
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