New  & Deprecated Features in 19c Data Guard

Below metioned are changes in Oracle Data Guard for Oracle Database Release 19c.

=> Replication of RestorePoint from Primary to Standby
The process of flashing back a physical standby to a point in time that was captured on the primary is simplified by automatically 
replicating restore points from primary to the standby.
 
=> Automatic Flashback of a Mounted Standby After a Primary RESETLOGS Operation
When flashback or point-in-time recovery is performed on the primary database, a standby that is in mounted mode can automatically 
follow the same recovery procedure performed on the primary. 

=> Performing DML Operations on Active Data Guard Standby Databases
DML operations can be performed on Active Data Guard standby instances. When an invalid PL/SQL object is run on an ADG standby database, 
the object is automatically recompiled.

=> Security Enhancement
A new  parameter, ADG_ACCOUNT_INFO_TRACKING, extends control of user account security against login attacks across a production 
database and all Oracle Active Data Guard standby databases.

=> View V$DATAGUARD_PROCESS
A new view V$DATAGUARD_PROCESS (which replaces V$MANAGED_STANDBY) provides information that can be queried to verify that redo is being 
transmitted from the primary database and applied to the standby database.

=> Logging Mode Extension
Database nologging has been extended with two new modes: 
1.Standby Nologging for Load Performance  
2.Standby Nologging for Data Availability. 
These modes provide better support for use in an Oracle ADG environment without significantly increasing the amount of redo generated. 

=> Rolling Forward a Standby using Network
A standby database can now be refreshed over the network using one RMAN command, RECOVER STANDBY DATABASE

=> Block Change Tracking 
Block Change Tracking is now supported with multi-instance redo apply.

Deprecated Attributes for LOG_ARCHIVE_DEST_n

The following attributes are deprecated for the LOG_ARCHIVE_DEST_n parameter. They are retained for backward compatibility only

Using Real-Time Apply to Apply Redo Data Immediately

Use the ALTER DATABASE statement to enable the real-time apply feature, as follows:

=> For physical standby databases, issue the ALTER DATABASE RECOVER MANAGED STANDBY DATABASE statement.
(As of Oracle Database 12c Release 1 (12.1), the USING CURRENT LOGFILE clause is deprecated and no longer necessary to start real-time apply.)
=> For logical standby databases, issue the ALTER DATABASE START LOGICAL STANDBY APPLY IMMEDIATE statement.

Real-time apply requires a standby database that is configured with a standby redo log and that is in ARCHIVELOG mode.