[PHOENIX-6186] Store table metadata last modified timestamp in PTable / System.Catalog

• Type: New Feature
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 5.1.0, 4.16.0
• Release Note: Introduces a new field in System.Catalog, LAST_DDL_TIMESTAMP, which is the epoch timestamp at which a table or view is created, or last had a column added or dropped. Child views inherit the max ddl timestamp of their ancestors.
• Assignee: Geoffrey Jacoby
• Reporter: Geoffrey Jacoby
• Created: 13/Oct/20 19:54
• Updated: 20/Nov/20 23:10
• Resolved: 20/Nov/20 23:10

Description

There are many reasons why it's useful to know when a particular table's metadata was last modified. It's helpful when solving cache coherency problems, and also in order to interact with external schema registries which may have multiple versions of a particular schema and require a timestamp to resolve ambiguities.

This JIRA will add a last modified timestamp field to System.Catalog, to be updated both when creating a table/view and also when adding or removing a column. Changing purely internal Phoenix properties will not update the timestamp.

Issue Links

• is required by: PHOENIX-5435 Annotate HBase WALs with Phoenix Metadata
• links to: GitHub Pull Request #935
• links to: GitHub Pull Request #977