[CASSANDRA-18358] Fix issue with system.local.broadcast_port when downgrading to v3

• Type: Bug
• Status: Triage Needed
• Priority: Normal
• Resolution: Unresolved
• Epic Link: Ability to downgrade
• Platform: All
• Assignee: Claude Warren
• Reporter: Claude Warren

Authors

Claude Warren

• Created: 23/Mar/23 14:13
• Updated: 23/Jun/23 04:44

Description

system.local table 4.0 format adds the broadcast_port column.  There is no way to make 3.x ignore it when we try to downgrade.

There are some tables that are defined in code. (e.g. system.local)

When v3 sstable schema for these tables detects:

• a column in the sstable schema that is not in the data schema it creates a deleted column in the data schema.
• a column in the data schema that is not in the sstable schema it throws an exception.

 

There are two basic approaches to solve this:

• rewrite the data so that the additional column is removed.  This is an expensive process.
• rework the code so that columns in the data but not in the table are ignored for this class of tables (statically defined in code).

Issue Links

• blocks: CASSANDRA-8928 Add downgradesstables