refactor: 분리되어 관리하고 있던 문서 시스템을 하나로 통일

2026-09-04 18:56:01 +09:00
parent 4b9e7148b5
commit 43bccd08a8
121 changed files with 2861 additions and 534 deletions
@@ -0,0 +1,18 @@
+-- L16 (c) precompute (CQRS read model) — per-viewer feed_visible table, single covering index scan
+-- FeedVisibilityIT.l16ExplainThreeWayPlanCompare / l16PrecomputeIsSingleIndexScanNoOrNoSort (seed 2000)
+-- CREATE TABLE feed_visible AS SELECT :me AS viewer_id, fi.id AS feed_item_id, fi.first_highlighted_at
+--   FROM feed_items fi WHERE <visible to me>;
+-- CREATE INDEX ix_feed_visible ON feed_visible (viewer_id, first_highlighted_at DESC, feed_item_id DESC);
+-- SELECT feed_item_id AS id, first_highlighted_at FROM feed_visible
+--   WHERE viewer_id=:me ORDER BY first_highlighted_at DESC, feed_item_id DESC LIMIT 20
+-- 읽기 포인트: 단일 Index Only Scan(커버링) — OR 도 조인도 Sort 도 없다. buffers shared hit=1(+2 read),
+--            훑는 행 20. 단일 OR(122)·UNION(200) 대비 order-of-magnitude 적음 = CQRS 읽기 모델의 정체.
+
+Limit  (cost=0.28..1.84 rows=20 width=24) (actual time=0.021..0.025 rows=20 loops=1)
+  Buffers: shared hit=1 read=2
+  ->  Index Only Scan using ix_feed_visible on feed_visible  (cost=0.28..117.22 rows=1500 width=24) (actual time=0.021..0.023 rows=20 loops=1)
+        Index Cond: (viewer_id = :me)
+        Heap Fetches: 20
+        Buffers: shared hit=1 read=2
+Planning Time: 0.102 ms
+Execution Time: 0.034 ms