lesson_ratings

Like / dislike ratings on lessons by learners.

• ETL strategy: merge
• PK: id

Columns

Column	Type	Description
id	BIGINT	PK.
id_tenant	BIGINT	FK → tenants.id.
id_product	BIGINT	FK → products.id.
id_lesson	BIGINT	FK → lessons.id.
id_user	BIGINT	FK → users.id.
vote	SMALLINT	Like / dislike. Enum — see below.
created_at	TIMESTAMPTZ

No deleted_at. To "remove" a rating, the system deletes the row (no soft-delete). Account for that when auditing.

Enum · vote

Value	Meaning
1	Like (positive vote).
-1	Dislike (negative vote).

Patterns

-- Best-rated lessons
SELECT id_lesson,
       count(*)                              AS total,
       sum((vote =  1)::int)                 AS likes,
       sum((vote = -1)::int)                 AS dislikes,
       round(avg(vote)::numeric, 3)          AS score
FROM lms.lesson_ratings
GROUP BY id_lesson
HAVING count(*) >= 10
ORDER BY score DESC, total DESC;

A pre-aggregated view exists: metrics.lesson_rating_aggregates.