some performance related index

[alphatownsman]

CREATE INDEX CONCURRENTLY idx_activities_post_author_published 
ON activities_post (
    author_id, 
    published DESC
) 
WHERE state NOT IN ('deleted', 'deleted_fanned_out');

CREATE INDEX CONCURRENTLY idx_timelineevent_identity_type_created 
ON activities_timelineevent (identity_id, type, created DESC);

CREATE INDEX CONCURRENTLY idx_journal_rating_item_grade 
ON journal_rating (item_id, grade) 
WHERE grade IS NOT NULL;

CREATE INDEX CONCURRENTLY idx_shelf_ctype_group ON journal_shelfmember (owner_id, parent_id) 
INCLUDE (item_id);