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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...

Problem - Automatic Workload Repository (AWR) snapshots cannot be taken in a read-only standby environment. - Performance monitoring and analysis is limited to basic STATSPACK functionality . Solution In Oracle Database 12.2 , the AWR framework is enhanced to support capture of remote snapshots from any generic database, including Active Data Guard (ADG) databases. This framework is called the Remote Management Framework (RMF). • A target catalog database collects snapshots from the remote databases (sources). • Snapshots can be collected automatically or manually. • AWR tables on the catalog database accumulate snapshot data from all sources via database links. • Source databases must be registered on the catalog via new DBMS_WORKLOAD_REPOSITORY.REGISTER_REMOTE_DATABASE API These are the basic steps for setting up the RMF topology for generating AWR on the physical standby: 1. Configure database nodes to add to the topology. 2. Create the topology. 3. Register database...

I have just came across a meta parameter called DB_ULTRA_SAFE that sets the values for all of mentioned parameters in Far Sync Best Practice Recommendations (for Oracle 12.1) . When DB_ULTRA_SAFE=DATA_ONLY   • DB_BLOCK_CHECKING => MEDIUM.   • DB_LOST_WRITE_PROTECT => TYPICAL.   • DB_BLOCK_CHECKSUM => FULL. When DB_ULTRA_SAFE=DATA_AND_INDEX   • DB_BLOCK_CHECKING => FULL.   • DB_LOST_WRITE_PROTECT => TYPICAL.   • DB_BLOCK_CHECKSUM => FULL. When DB_ULTRA_SAFE=OFF   • When any of DB_BLOCK_CHECKING, DB_BLOCK_CHECKSUM, or DB_LOST_WRITE_PROTECT are explicitly set, no changes are made.

Hi, At Oracle Open World 2017 I collected the main improvements and changes  are going to be implemented in Oracle Database 18c: RMAN - Refresh a standby from primary/backup using single RECOVER command Data Guard - In Memory Column store works with multi-instance redo apply - Multi-instance redo apply support with Block Change Tracking (BCT) - Global Temporary Table support from Standby. - DML operations on Standby – Redirection to Primary without ACID compromise. - Preserve buffer cache during role-change. - No logging enhancement - Performance mode and Availability mode. Yossi Nixon