[CASSANDRA-15501] Duplicate results with DISTINCT queries in mixed mode 2.1/3.0

• Type: Bug
• Status: Resolved
• Priority: Normal
• Resolution: Fixed
• Fix Version/s: 2.2.17, 3.0.21, 3.11.7, 4.0-beta1, 4.0
• Component/s: Legacy/Core
• Bug Category: Correctness - Transient Incorrect Response
• Severity: Normal
• Complexity: Normal
• Discovered By: Adhoc Test
• Platform: All
• Since Version: 3.0 alpha 1

Source Control Link

https://github.com/apache/cassandra/commit/16f639af94f56cdc7145299730278e27a9113e2e

Test and Documentation Plan

new upgrade test & cci runs

• Assignee: Marcus Eriksson
• Reporter: Marcus Eriksson

Authors

Marcus Eriksson

Reviewers

Aleksey Yeschenko, Alex Petrov, Sam Tunnicliffe

• Created: 13/Jan/20 08:03
• Updated: 15/May/20 08:53
• Resolved: 16/Apr/20 11:02

Description

When a client switches coordinator from a 2.1 node to a 3.0 node it sends a 2.1 paging state to the 3.0 node. The 2.1 PagingState does not have remainingInPartition so on the 3.0 side we default this to Integer.MAX_VALUE. This value is then used to decide if the lastKey should be included in the result.