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Previously, you could only update Global Temp Tables on Active Data Guard standby database. From Oracle  19c , you can also update regular tables. Updates on Active Data Guard: Update will be redirected to the primary Primary makes update, generates & sends redo for that update to all standbys Active Data Guard session sees the update in redo apply and resumes Preserves ACID properties for ADG session Redirected update only visible to session before commit; visible to all sessions after commit For “Mostly Read, Occasional Updates ” applications – for example, recording user logins for auditing purposes Enabled by ADG_REDIRECT_DML at system or session level The following setup is based on Active Data guard configuration is MaxAvailability, but the behavior is the same when configuring MaxPerformance A step by step guide to demonstrate this feature: Current configuration Basic setup  The setup is primary database sends its redo logfiles through a f...

Send redo data from Primary database if MOUNT is possible. ALTER SYSTEM FLUSH REDO TO target_db_name; At Standby, if Flashback Database is not already enabled: ALTER DATABASE RECOVER MANAGED STANDBY DATABASE CANCEL; ALTER SYSTEM SET DB_FLASHBACK_RETENTION_TARGET=4320; # 3 days ALTER DATABASE FLASHBACK ON; Create a restore point BEFORE_FAILOVER, The restore point will be used later to restore the database again to the same state before FAILOVER scenario. set lines 300 ALTER DATABASE RECOVER MANAGED STANDBY DATABASE CANCEL; CREATE RESTORE POINT before_failover GUARANTEE FLASHBACK DATABASE; SELECT scn, guarantee_flashback_database, name FROM v$restore_point; SCN GUARANTEE_FLASHBACK_DATABASE NAME ------- ---------------------------- ---------------- 2619073 YES BEFORE_FAILOVER Testing FAILOVER on physical standby database STBY. SELECT name, db_unique_name, log_mode, protection_mode, database_role FROM v$database; NAME DB_UNIQUE_...