[HIVE-16785] Ensure replication actions are idempotent if any series of events are applied again.

• Type: Sub-task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.1.0
• Fix Version/s: 3.0.0
• Component/s: Hive, repl
• Labels: DR replication
• Assignee: Sankar Hariappan
• Reporter: Sankar Hariappan
• Created: 30/May/17 07:27
• Updated: 23/May/18 00:00
• Resolved: 29/Jun/17 06:58

Description

Some of the events(ALTER, RENAME, TRUNCATE) are not idempotent and hence leads to failure of REPL LOAD if applied twice or applied on an object which is latest than current event. For example, if TRUNCATE is applied on a table which is already dropped will fail instead of noop.
Also, need to consider the scenario where the object is missing while applying an event. For example, if RENAME_TABLE event is applied on target where the old table is missing should validate if table should be recreated or should treat the event as noop. This can be done by verifying the DB level last repl ID against the current event ID.

Issue Links

• links to: GitHub Pull Request #194