[CASSANDRA-6038] Support schema changes in mixed version clusters

• Type: Sub-task
• Status: Open
• Priority: Normal
• Resolution: Unresolved
• Fix Version/s: 5.x
• Component/s: Legacy/Distributed Metadata
• Impacts: Clients
• Assignee: Unassigned
• Reporter: Aleksey Yeschenko
• Created: 17/Sep/13 09:33
• Updated: 07/Mar/23 10:54

Description

CASSANDRA-5845 made it so that schema changes in a major-mixed cluster are not propagated to the minorer-major nodes. This lets us perform backwards-incompatible schema changes in major releases safely - like adding the schema_triggers table, moving all the aliases to schema_columns, getting rid of the deprecated schema columns, etc.

Even this limitation might be too strict, however, and should be avoided if possible (starting with at least versioning schema separately from messaging service versioning, and resorting to major->minor schema block only when truly necessary and not for every x->y pair).

Issue Links

• is related to: CASSANDRA-7734 Schema pushes (seemingly) randomly not happening
• relates to: CASSANDRA-7697 UDF use new schema migration