perf: 优化 dashboard 的查询性能 (#393)

crates/bili_sync/src/api/routes/dashboard/mod.rs

@@ -34,35 +34,25 @@ async fn get_dashboard(
             // 用 SeaORM 太复杂了，直接写个裸 SQL
             "
 SELECT
-	dates.day AS day,
-	COUNT(video.id) AS cnt
+    dates.day AS day,
+    COUNT(video.id) AS cnt
 FROM
-	(
-		SELECT
-			STRFTIME(
-				'%Y-%m-%d',
-			DATE('now', '-' || n || ' days', 'localtime')) AS day
-		FROM
-			(
-				SELECT
-					0 AS n UNION ALL
-				SELECT
-					1 UNION ALL
-				SELECT
-					2 UNION ALL
-				SELECT
-					3 UNION ALL
-				SELECT
-					4 UNION ALL
-				SELECT
-					5 UNION ALL
-				SELECT
-			6)) AS dates
-	LEFT JOIN video ON STRFTIME('%Y-%m-%d', video.created_at, 'localtime') = dates.day
+    (
+        SELECT
+            STRFTIME('%Y-%m-%d', DATE('now', '-' || n || ' days', 'localtime')) AS day,
+            DATETIME(DATE('now', '-' || n || ' days', 'localtime'), 'utc') AS start_utc_datetime,
+            DATETIME(DATE('now', '-' || n || ' days', '+1 day', 'localtime'), 'utc') AS end_utc_datetime
+        FROM
+            (
+                SELECT 0 AS n UNION ALL SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6
+            )
+    ) AS dates
+LEFT JOIN
+    video ON video.created_at >= dates.start_utc_datetime AND video.created_at < dates.end_utc_datetime
 GROUP BY
-	dates.day
+    dates.day
 ORDER BY
-	dates.day;
+    dates.day;
     "
         ))
         .all(db.as_ref()),

crates/bili_sync_migration/src/lib.rs

@@ -7,6 +7,7 @@ mod m20240724_161008_submission;
 mod m20250122_062926_add_latest_row_at;
 mod m20250612_090826_add_enabled;
 mod m20250613_043257_add_config;
+mod m20250712_080013_add_video_created_at_index;
 
 pub struct Migrator;
 
@@ -21,6 +22,7 @@ impl MigratorTrait for Migrator {
             Box::new(m20250122_062926_add_latest_row_at::Migration),
             Box::new(m20250612_090826_add_enabled::Migration),
             Box::new(m20250613_043257_add_config::Migration),
+            Box::new(m20250712_080013_add_video_created_at_index::Migration),
         ]
     }
 }

crates/bili_sync_migration/src/m20250712_080013_add_video_created_at_index.rs

@@ -0,0 +1,36 @@
+use sea_orm_migration::prelude::*;
+
+#[derive(DeriveMigrationName)]
+pub struct Migration;
+
+#[async_trait::async_trait]
+impl MigrationTrait for Migration {
+    async fn up(&self, manager: &SchemaManager) -> Result<(), DbErr> {
+        manager
+            .create_index(
+                Index::create()
+                    .table(Video::Table)
+                    .name("video_created_at_index")
+                    .col(Video::CreatedAt)
+                    .to_owned(),
+            )
+            .await
+    }
+
+    async fn down(&self, manager: &SchemaManager) -> Result<(), DbErr> {
+        manager
+            .drop_index(
+                Index::drop()
+                    .table(Video::Table)
+                    .name("video_created_at_index")
+                    .to_owned(),
+            )
+            .await
+    }
+}
+
+#[derive(DeriveIden)]
+enum Video {
+    Table,
+    CreatedAt,
+}