[PHOENIX-6035] Extend phoenix.allow.system.catalog.rollback or introduce a new config to completely rollback changes introduced by Splittable SYSTEM.CATALOG

• Type: Improvement
• Status: Open
• Priority: Critical
• Resolution: Unresolved
• Affects Version/s: 5.0.0, 4.15.0
• Fix Version/s: 4.17.0, 4.16.2
• Assignee: Unassigned
• Reporter: Chinmay Kulkarni
• Created: 22/Jul/20 21:36
• Updated: 21/May/21 16:27

Description

Currently, https://issues.apache.org/jira/browse/PHOENIX-3534 just makes sure that SYSTEM.CATALOG does not split and continues writing parent column metadata with view metadata. Clients that want 4.15/4.x features without needing SYSTEM.CATALOG to be splittable can already just provide phoenix.system.catalog.splittable=false. We should extend the phoenix.allow.system.catalog.rollback config so that when it is true, it will include the following:

• Continue writing parent->child links to SYSTEM.CATALOG instead of using SYSTEM.CHILD_LINK
• Not use SYSTEM.TASK for dropping child views but directly issue the drop view commands since SYSTEM.CATALOG is on a single region anyways
• In the upgrade path for 4.16, if this config is on, we will have to reliably also do the following:

1. Move all parent->child links from SYSTEM.CHILD_LINK to SYSTEM.CATALOG
2. Clean the SYSTEM.TASK table and execute all unscheduled DropChildViewsTask tasks

Basically, for a 4.15 client with phoenix.allow.system.catalog.rollback=true, at the end of their upgrade to 4.16, the SYSTEM.CHILD_LINK table should be empty and unused henceforth and the SYSTEM.TASK table should not contain any DropChildViewsTask tasks and should be unused for the purpose of DROP TABLE/VIEW <parent table/view name> CASCADE DDLs henceforth.

Issue Links

• is a parent of: PHOENIX-6036 Introduce a new statement to rollback Splittable SYSTEM.CATALOG changes when phoenix.allow.system.catalog.rollback=true