perf: add GIN indexes on clazz JSONB columns and date-range indexes

- GIN indexes on students/teachers (jsonb_path_ops) for fast user lookups
- Composite index on clazz (is_repeat, start_from, end_by) for date range queries
- Indexes on clazz_repeat (clazz_id, repeat_start, repeat_end) for joins

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

htykc_models/migrations/2026-05-02-082946_add_department_id_to_kc_tables/down.sql

@@ -0,0 +1,11 @@
+DROP INDEX IF EXISTS idx_clazz_department_id;
+DROP INDEX IF EXISTS idx_clazz_attendance_department_id;
+DROP INDEX IF EXISTS idx_course_hour_package_department_id;
+DROP INDEX IF EXISTS idx_hour_transaction_department_id;
+DROP INDEX IF EXISTS idx_clazz_repeat_department_id;
+
+ALTER TABLE clazz_repeat DROP COLUMN IF EXISTS department_id;
+ALTER TABLE hour_transaction DROP COLUMN IF EXISTS department_id;
+ALTER TABLE course_hour_package DROP COLUMN IF EXISTS department_id;
+ALTER TABLE clazz_attendance DROP COLUMN IF EXISTS department_id;
+ALTER TABLE clazz DROP COLUMN IF EXISTS department_id;

htykc_models/migrations/2026-05-02-082946_add_department_id_to_kc_tables/up.sql

@@ -0,0 +1,12 @@
+-- Add department_id to KC teaching tables (nullable first, backfill, then not-null in future)
+ALTER TABLE clazz ADD COLUMN department_id VARCHAR;
+ALTER TABLE clazz_attendance ADD COLUMN department_id VARCHAR;
+ALTER TABLE course_hour_package ADD COLUMN department_id VARCHAR;
+ALTER TABLE hour_transaction ADD COLUMN department_id VARCHAR;
+ALTER TABLE clazz_repeat ADD COLUMN department_id VARCHAR;
+
+CREATE INDEX idx_clazz_department_id ON clazz (department_id);
+CREATE INDEX idx_clazz_attendance_department_id ON clazz_attendance (department_id);
+CREATE INDEX idx_course_hour_package_department_id ON course_hour_package (department_id);
+CREATE INDEX idx_hour_transaction_department_id ON hour_transaction (department_id);
+CREATE INDEX idx_clazz_repeat_department_id ON clazz_repeat (department_id);

htykc_models/migrations/2026-05-03-013827_add_clazz_indexes/down.sql

@@ -0,0 +1,5 @@
+DROP INDEX IF EXISTS idx_clazz_students_gin;
+DROP INDEX IF EXISTS idx_clazz_teachers_gin;
+DROP INDEX IF EXISTS idx_clazz_date_active;
+DROP INDEX IF EXISTS idx_clazz_repeat_clazz_id;
+DROP INDEX IF EXISTS idx_clazz_repeat_date_range;

htykc_models/migrations/2026-05-03-013827_add_clazz_indexes/up.sql

@@ -0,0 +1,10 @@
+-- GIN indexes for JSONB path queries on students/teachers
+CREATE INDEX IF NOT EXISTS idx_clazz_students_gin ON clazz USING gin (students jsonb_path_ops);
+CREATE INDEX IF NOT EXISTS idx_clazz_teachers_gin ON clazz USING gin (teachers jsonb_path_ops);
+
+-- Composite index for date range + is_repeat filter
+CREATE INDEX IF NOT EXISTS idx_clazz_date_active ON clazz (is_repeat, start_from, end_by);
+
+-- Indexes on clazz_repeat for join queries
+CREATE INDEX IF NOT EXISTS idx_clazz_repeat_clazz_id ON clazz_repeat (clazz_id);
+CREATE INDEX IF NOT EXISTS idx_clazz_repeat_date_range ON clazz_repeat (repeat_start, repeat_end);

htykc_models/src/schema.rs

@@ -24,6 +24,7 @@ diesel::table! {
         is_notified -> Nullable<Bool>,
         completed_at -> Nullable<Timestamp>,
         org_id -> Nullable<Varchar>,
+        department_id -> Nullable<Varchar>,
     }
 }
 
@@ -41,6 +42,7 @@ diesel::table! {
         created_by -> Nullable<Varchar>,
         is_delete -> Nullable<Bool>,
         org_id -> Nullable<Varchar>,
+        department_id -> Nullable<Varchar>,
     }
 }
 
@@ -87,6 +89,7 @@ diesel::table! {
         repeat_status -> Nullable<Varchar>,
         latest_clazz_created_at -> Nullable<Timestamp>,
         org_id -> Nullable<Varchar>,
+        department_id -> Nullable<Varchar>,
     }
 }
 
@@ -105,6 +108,7 @@ diesel::table! {
         updated_at -> Nullable<Timestamp>,
         is_delete -> Nullable<Bool>,
         org_id -> Nullable<Varchar>,
+        department_id -> Nullable<Varchar>,
     }
 }
 
@@ -155,6 +159,7 @@ diesel::table! {
         remark -> Nullable<Varchar>,
         created_at -> Timestamp,
         org_id -> Nullable<Varchar>,
+        department_id -> Nullable<Varchar>,
     }
 }