By andypost on
Change record status: 
Published (View all published change records)
Project: 
Drupal core
Introduced in branch: 
8.x
Introduced in version: 
8.0
Issue links: 
https://www.drupal.org/node/1498662
Description: 

Comment properties have been converted to support language variance on properties such as subject. This is using the standard multilingual variance capability for properties that was introduced earlier.

  • The {comment} base table only holds
    | cid* | uuid | comment_type | langcode |
    Primary key: cid
  • New {comment_field_data} table is introduced for property data per language.
    | cid* | comment_type | langcode* | default_langcode | pid | entity_id | subject | uid | name | mail | homepage | hostname | created | changed | status | thread | entity_type | field_name |
    • Primary key ({comment_field_data}): cid + langcode

For further details read Added multilingual support to the standard entity schema.

The main difference with the standard described above is that the bundle column ({comment_type}) has been replicated in the {comment_field_data} table to keep the related index and avoid a performance degradation for certain queries.

Impacts: 
Module developers