wf_task_comment Task Comments

The engine's only "guestbook": one approval comment per row, append-only. After the task row completes and is migrated into the history tables, comments remain queryable and appendable in place — the audit trail is an independent timeline that does not move with the task.

Table Structure

Field	Type	Description
id	VARCHAR(36) PK	Primary key
task_id	VARCHAR(36)	References wf_task.id (still commentable/queryable after the task is archived)
process_instance_id	VARCHAR(36)	Process instance ID; pull the full comment stream of a process by instance
tenant_id	VARCHAR(100)	Tenant ID
user_id	VARCHAR(64)	Commenter ID
user_name	VARCHAR(100)	Commenter name (stored redundantly to avoid joins)
content	TEXT	Comment content
created_at	TIMESTAMPTZ	Creation time

Indexes: task_id, tenant_id.

Why Comments Don't Live on the Task Row

wf_task.comment stores only the conclusive comment from the last handling action, snapshotted into wf_hi_task when the task is archived. But a task's lifecycle often involves more than one comment: every countersign participant leaves one, add-signed approvers need to state their position too, and a reject-and-redo round adds another pass — this is a continuously appended timeline that a single field cannot hold.

So comments live in their own table: one comment per row — who (user_id / user_name), when (created_at), and what was said (content), attached by task_id. Append-only: historical comments are never overwritten by later handling.

Still Readable and Writable After the Task Is Archived

Once runtime-table data completes, it migrates wholesale into wf_hi_*, whereas wf_task_comment is a persistent table: task_id is only a logical association — the task row moves away, the comments stay where they are. Completed-task detail views read it as usual, and adding a comment after the fact is no problem. To view a whole process's approval trail, pull everything at once via process_instance_id.

Usage Examples

-- All comments of a task (chronological order)
SELECT user_name, content, created_at
FROM wf_task_comment
WHERE task_id = '...'
ORDER BY created_at;

-- The complete approval comment stream of a process instance
SELECT task_id, user_name, content, created_at
FROM wf_task_comment
WHERE process_instance_id = '...'
ORDER BY created_at;

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