[CASSANDRA-18760] Backport CASSANDRA-16905 to older branches

• Type: Bug
• Status: Resolved
• Priority: Urgent
• Resolution: Fixed
• Fix Version/s: 3.0.30, 3.11.16, 4.0.12
• Component/s: Cluster/Schema
• Labels: 4.0.10
• Bug Category: Correctness - Unrecoverable Corruption / Loss
• Severity: Normal
• Complexity: Normal
• Discovered By: User Report
• Platform: Linux
• Since Version: NA

Source Control Link

https://github.com/apache/cassandra/commit/f0280fb6f863582125bfd16b8a90c345972c4a8c

Test and Documentation Plan

CI

• Assignee: Stefan Miklosovic
• Reporter: Paul Ayers

Authors

Stefan Miklosovic

Reviewers

Andres de la Peña

• Created: 15/Aug/23 20:54
• Updated: 18/Aug/23 18:02
• Resolved: 18/Aug/23 18:01

Description

Recently hit an un-recoverable situation in Cassandra 4.0.10 after dropping a 'map' column and adding it back as a 'blob', which caused corruption that neither offline nor online scrub could fix.
When dropping a 'blob' column and attempting to add it back as a 'map' type, the operation is blocked with:

InvalidRequest: Error from server: code=2200 [Invalid query] message="Cannot re-add previously dropped column 'col1' of type map<int, tinyint>, incompatible with previous type blob"

We need to do the same going from 'map' to 'blob' to avoid this potentially very bad scenario that can cause data loss.

Issue Links

• is related to: CASSANDRA-16905 Further restrict schema column drop/recreate conversions
• links to: GitHub Pull Request #2600
• links to: GitHub Pull Request #2602
• links to: GitHub Pull Request #2603
• links to: GitHub Pull Request #2604
• links to: GitHub Pull Request #2607
• links to: GitHub Pull Request #2608