测试与优化

性能测试/优化sql测试文件.sql

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+-- ============================================
+-- 功能04优化：医生当日待诊列表
+-- ============================================
+WITH schedule_ids AS (
+    SELECT schedule_id
+    FROM schedule
+    WHERE doctor_id = '550e8400-e29b-41d4-a716-446655440004'
+      AND work_date = '2024-12-15'
+),
+     appointment_data AS (
+         SELECT a.appointment_id, a.patient_id, a.appointment_time
+         FROM appointment a
+         WHERE a.schedule_id IN (SELECT schedule_id FROM schedule_ids)
+           AND a.status = 'scheduled'
+     )
+SELECT
+    ad.appointment_id,
+    p.name AS patient_name,
+    ad.appointment_time
+FROM appointment_data ad
+         JOIN patient p ON ad.patient_id = p.patient_id
+ORDER BY ad.appointment_time;
+
+-- ============================================
+-- 功能13优化：扣减药品库存
+-- ============================================
+-- 优化后（使用索引覆盖）
+CREATE INDEX idx_inventory_batch_drug_stock_expiry_covering
+    ON inventory_batch(drug_id, current_stock, expiry_date)
+    INCLUDE (batch_id);
+
+-- 然后使用索引优化查询
+EXPLAIN (ANALYZE, VERBOSE)
+SELECT batch_id
+FROM inventory_batch
+WHERE drug_id = '550e8400-e29b-41d4-a716-446655440018'
+  AND current_stock >= 10
+ORDER BY expiry_date
+LIMIT 1;
+
+-- ============================================
+-- 功能18优化：统计医生工作量
+-- ============================================
+-- 优化后（使用日期范围，可索引优化）
+SELECT d.name,
+       COUNT(mr.record_id) as record_count
+FROM doctor d
+         LEFT JOIN medical_record mr ON d.doctor_id = mr.doctor_id
+    AND mr.visit_time >= '2024-12-01'::date
+    AND mr.visit_time < '2025-01-01'::date
+WHERE d.work_status = 'active'
+GROUP BY d.doctor_id, d.name;
+
+-- ============================================
+-- 功能16优化：查询库存预警药品
+-- ============================================
+-- 优化后（使用子查询减少JOIN）
+WITH drug_stock AS (
+    SELECT
+        drug_id,
+        SUM(current_stock) as total_stock,
+        MIN(min_stock_threshold) as min_threshold
+    FROM inventory_batch
+    GROUP BY drug_id
+    HAVING SUM(current_stock) < MIN(min_stock_threshold)
+)
+SELECT
+    d.generic_name,
+    ds.total_stock,
+    ds.min_threshold
+FROM drug_stock ds
+         JOIN drug d ON ds.drug_id = d.drug_id;
+
+-- ============================================
+-- 功能16优化：查询库存预警药品
+-- ============================================
+-- 优化后（减少JOIN层级，使用子查询）
+SELECT
+    dep.name,
+    COALESCE(apt_stats.appointment_count, 0) as appointment_count
+FROM department dep
+         LEFT JOIN (
+    SELECT
+        d.department_id,
+        COUNT(a.appointment_id) as appointment_count
+    FROM doctor d
+             JOIN schedule s ON d.doctor_id = s.doctor_id
+             LEFT JOIN appointment a ON s.schedule_id = a.schedule_id
+    WHERE s.work_date = '2024-12-15'
+    GROUP BY d.department_id
+) apt_stats ON dep.department_id = apt_stats.department_id
+ORDER BY dep.name;

性能测试/优化sql测试结果.md

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+### 索引优化策略
+
+```sql
+-- 1. 排班表索引优化
+CREATE INDEX IF NOT EXISTS idx_schedule_doctor_date_remain 
+ON schedule(doctor_id, work_date, remaining_appointments);
+
+-- 2. 预约表索引优化
+CREATE INDEX IF NOT EXISTS idx_appointment_schedule_status_time 
+ON appointment(schedule_id, status, appointment_time);
+
+CREATE INDEX IF NOT EXISTS idx_appointment_status 
+ON appointment(status);
+
+-- 3. 库存批次表索引优化
+CREATE INDEX IF NOT EXISTS idx_inventory_batch_drug_stock_expiry 
+ON inventory_batch(drug_id, current_stock, expiry_date);
+
+-- 4. 药品表索引优化（已有主键索引）
+CREATE INDEX IF NOT EXISTS idx_drug_generic_name 
+ON drug(generic_name);
+
+-- 5. 医生表索引优化
+CREATE INDEX IF NOT EXISTS idx_doctor_status 
+ON doctor(work_status);
+
+-- 6. 电子病历表索引优化
+CREATE INDEX IF NOT EXISTS idx_medical_record_doctor_visit 
+ON medical_record(doctor_id, visit_time);
+
+-- 7. 处方明细表索引优化
+CREATE INDEX IF NOT EXISTS idx_prescription_item_prescription 
+ON prescription_item(prescription_id);
+
+-- 8. 患者表索引优化
+CREATE INDEX IF NOT EXISTS idx_patient_name 
+ON patient(name);
+```
+
+### 查询重写优化
+
+#### 功能04优化：医生当日待诊列表
+```sql
+-- 优化前（存在Seq Scan）
+EXPLAIN (ANALYZE, VERBOSE)
+SELECT a.appointment_id, p.name AS patient_name, a.appointment_time
+FROM appointment a
+JOIN patient p ON a.patient_id = p.patient_id
+JOIN schedule s ON a.schedule_id = s.schedule_id
+WHERE s.doctor_id = '550e8400-e29b-41d4-a716-446655440004' 
+  AND s.work_date = '2024-12-15' 
+  AND a.status = 'scheduled'
+ORDER BY a.appointment_time;
+
+-- 优化后（使用CTE和优化JOIN顺序）
+WITH schedule_ids AS (
+    SELECT schedule_id 
+    FROM schedule 
+    WHERE doctor_id = '550e8400-e29b-41d4-a716-446655440004' 
+      AND work_date = '2024-12-15'
+),
+appointment_data AS (
+    SELECT a.appointment_id, a.patient_id, a.appointment_time
+    FROM appointment a
+    WHERE a.schedule_id IN (SELECT schedule_id FROM schedule_ids)
+      AND a.status = 'scheduled'
+)
+SELECT 
+    ad.appointment_id,
+    p.name AS patient_name,
+    ad.appointment_time
+FROM appointment_data ad
+JOIN patient p ON ad.patient_id = p.patient_id
+ORDER BY ad.appointment_time;
+```
+
+|   |   |   |   |   |   |   |   |   |
+|---|---|---|---|---|---|---|---|---|
+|SELECT (select)||||||||Planning Time = 0.323; Triggers = []; Execution Time = 0.031;|
+|SORT (sort)||1|0|17.18|0.012|17.17|0.012|Parallel Aware = false; Async Capable = false; Plan Width = 32; Actual Loops = 1; Sort Key = ["a.appointment_time"]; Sort Method = quicksort; Sort Space Used = 25; Sort Space Type = Memory;|
+|NESTED_LOOPS (Nested Loop)||1|0|17.16|0.008|0.98|0.008|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Join Type = Inner; Plan Width = 32; Actual Loops = 1; Inner Unique = true;|
+|NESTED_LOOPS (Nested Loop)||1|0|16.75|0.008|0.7|0.008|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Join Type = Inner; Plan Width = 40; Actual Loops = 1; Inner Unique = false;|
+|INDEX_SCAN (index scan)|table: schedule; index: idx_schedule_doctor_date_remain;|1|0|8.31|0.008|0.29|0.008|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Scan Direction = Forward; Alias = schedule; Plan Width = 16; Actual Loops = 1; Index Cond = ((doctor_id = '550e8400-e29b-41d4-a716-446655440004'::uuid) AND (work_date = '2024-12-15'::date)); Rows Removed by Index Recheck = 0;|
+|INDEX_SCAN (index scan)|table: appointment; index: idx_appointment_schedule_status_time;|1|0|8.43|0.0|0.41|0.0|Parent Relationship = Inner; Parallel Aware = false; Async Capable = false; Scan Direction = Forward; Alias = a; Plan Width = 56; Actual Loops = 0; Index Cond = ((schedule_id = schedule.schedule_id) AND ((status)::text = 'scheduled'::text)); Rows Removed by Index Recheck = 0;|
+|INDEX_SCAN (index scan)|table: patient; index: patient_pkey;|1|0|0.41|0.0|0.29|0.0|Parent Relationship = Inner; Parallel Aware = false; Async Capable = false; Scan Direction = Forward; Alias = p; Plan Width = 24; Actual Loops = 0; Index Cond = (patient_id = a.patient_id); Rows Removed by Index Recheck = 0;|
+#### 功能13优化：扣减药品库存
+```sql
+-- 优化前（全表扫描+排序）
+EXPLAIN (ANALYZE, VERBOSE)
+SELECT batch_id FROM inventory_batch
+WHERE drug_id = '550e8400-e29b-41d4-a716-446655440018' 
+  AND current_stock >= 10
+ORDER BY expiry_date ASC LIMIT 1;
+
+-- 优化后（使用索引覆盖）
+CREATE INDEX idx_inventory_batch_drug_stock_expiry_covering
+ON inventory_batch(drug_id, current_stock, expiry_date) 
+INCLUDE (batch_id);
+
+-- 然后使用索引优化查询
+EXPLAIN (ANALYZE, VERBOSE)
+SELECT batch_id 
+FROM inventory_batch
+WHERE drug_id = '550e8400-e29b-41d4-a716-446655440018' 
+  AND current_stock >= 10
+ORDER BY expiry_date ASC 
+LIMIT 1;
+```
+Limit  (cost=4.41..4.41 rows=1 width=20) (actual time=0.071..0.072 rows=0 loops=1)
+"  Output: batch_id, expiry_date"
+  ->  Sort  (cost=4.41..4.42 rows=5 width=20) (actual time=0.071..0.071 rows=0 loops=1)
+"        Output: batch_id, expiry_date"
+        Sort Key: inventory_batch.expiry_date
+        Sort Method: quicksort  Memory: 25kB
+        ->  Index Only Scan using idx_inventory_batch_drug_stock_expiry_covering on hms.inventory_batch  (cost=0.28..4.38 rows=5 width=20) (actual time=0.067..0.067 rows=0 loops=1)
+"              Output: batch_id, expiry_date"
+              Index Cond: ((inventory_batch.drug_id = '550e8400-e29b-41d4-a716-446655440018'::uuid) AND (inventory_batch.current_stock >= 10))
+              Heap Fetches: 0
+Planning Time: 1.619 ms
+Execution Time: 0.095 ms
+
+#### 功能18优化：统计医生工作量
+```sql
+-- 优化前（使用EXTRACT函数，无法使用索引）
+SELECT d.name, COUNT(mr.record_id) as record_count
+FROM doctor d
+LEFT JOIN medical_record mr ON d.doctor_id = mr.doctor_id 
+    AND EXTRACT(YEAR FROM mr.visit_time) = 2024
+    AND EXTRACT(MONTH FROM mr.visit_time) = 12
+WHERE d.work_status = 'active'
+GROUP BY d.doctor_id, d.name;
+
+-- 优化后（使用日期范围，可索引优化）
+SELECT 
+    d.name,
+    COUNT(mr.record_id) as record_count
+FROM doctor d
+LEFT JOIN medical_record mr ON d.doctor_id = mr.doctor_id 
+    AND mr.visit_time >= '2024-12-01'::date
+    AND mr.visit_time < '2025-01-01'::date
+WHERE d.work_status = 'active'
+GROUP BY d.doctor_id, d.name;
+
+```
+
+|   |   |   |   |   |   |   |   |   |
+|---|---|---|---|---|---|---|---|---|
+|SELECT (select)||||||||Planning Time = 0.244; Triggers = []; Execution Time = 1.622;|
+|AGGREGATE (aggregate)||1194|1194|2966.52|1.514|2954.58|1.446|Strategy = Hashed; Partial Mode = Simple; Parallel Aware = false; Async Capable = false; Plan Width = 32; Actual Loops = 1; Group Key = ["d.doctor_id"]; Planned Partitions = 0; HashAgg Batches = 1; Peak Memory Usage = 193; Disk Usage = 0;|
+|HASH_JOIN (hash join)||1194|1295|2948.61|1.284|672.45|0.725|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Join Type = Right; Plan Width = 40; Actual Loops = 1; Inner Unique = true; Hash Cond = (mr.doctor_id = d.doctor_id);|
+|BITMAP_INDEX_SCAN (Bitmap Heap Scan)|table: medical_record;|899|865|2878.32|0.834|604.52|0.414|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Alias = mr; Plan Width = 32; Actual Loops = 1; Recheck Cond = ((visit_time >= '2024-12-01'::date) AND (visit_time < '2025-01-01'::date)); Rows Removed by Index Recheck = 0; Exact Heap Blocks = 781; Lossy Heap Blocks = 0;|
+|BITMAP_INDEX_SCAN (bitmap index scan)|index: idx_medical_record_doctor_visit;|899|865|604.3|0.354|0.0|0.354|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Plan Width = 0; Actual Loops = 1; Index Cond = ((visit_time >= '2024-12-01'::date) AND (visit_time < '2025-01-01'::date));|
+|TRANSFORM (Hash)||1194|1194|53.0|0.303|53.0|0.303|Parent Relationship = Inner; Parallel Aware = false; Async Capable = false; Plan Width = 24; Actual Loops = 1; Hash Buckets = 2048; Original Hash Buckets = 2048; Hash Batches = 1; Original Hash Batches = 1; Peak Memory Usage = 82;|
+|SEQ_SCAN (Seq Scan)|table: doctor;|1194|1194|53.0|0.201|0.0|0.013|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Alias = d; Plan Width = 24; Actual Loops = 1; Filter = ((work_status)::text = 'active'::text); Rows Removed by Filter = 806;|
+#### 功能16优化：查询库存预警药品
+```sql
+-- 优化前（Hash Join + 全表扫描）
+SELECT d.generic_name, SUM(ib.current_stock) AS total_stock
+FROM drug d
+JOIN inventory_batch ib ON d.drug_id = ib.drug_id
+GROUP BY d.drug_id, d.generic_name, ib.min_stock_threshold
+HAVING SUM(ib.current_stock) < ib.min_stock_threshold;
+
+-- 优化后（使用子查询减少JOIN）
+WITH drug_stock AS (
+    SELECT 
+        drug_id,
+        SUM(current_stock) as total_stock,
+        MIN(min_stock_threshold) as min_threshold
+    FROM inventory_batch
+    GROUP BY drug_id
+    HAVING SUM(current_stock) < MIN(min_stock_threshold)
+)
+SELECT 
+    d.generic_name,
+    ds.total_stock,
+    ds.min_threshold
+FROM drug_stock ds
+JOIN drug d ON ds.drug_id = d.drug_id;
+```
+
+|   |   |   |   |   |   |   |   |   |
+|---|---|---|---|---|---|---|---|---|
+|SELECT (select)||||||||Planning Time = 1.723; Triggers = []; Execution Time = 1.241;|
+|HASH_JOIN (hash join)||331|0|231.01|1.191|194.37|1.19|Parallel Aware = false; Async Capable = false; Join Type = Inner; Plan Width = 21; Actual Loops = 1; Inner Unique = true; Hash Cond = (d.drug_id = ds.drug_id);|
+|SEQ_SCAN (Seq Scan)|table: drug;|1000|1|34.0|0.01|0.0|0.009|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Alias = d; Plan Width = 25; Actual Loops = 1;|
+|TRANSFORM (Hash)||331|0|190.24|1.176|190.24|1.175|Parent Relationship = Inner; Parallel Aware = false; Async Capable = false; Plan Width = 28; Actual Loops = 1; Hash Buckets = 1024; Original Hash Buckets = 1024; Hash Batches = 1; Original Hash Batches = 1; Peak Memory Usage = 8;|
+|ACCESS (Subquery Scan)||331|0|190.24|1.175|174.5|1.175|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Alias = ds; Plan Width = 28; Actual Loops = 1;|
+|AGGREGATE (aggregate)||331|0|186.93|1.175|174.5|1.175|Strategy = Hashed; Partial Mode = Simple; Parent Relationship = Subquery; Parallel Aware = false; Async Capable = false; Plan Width = 28; Actual Loops = 1; Group Key = ["inventory_batch.drug_id"]; Filter = (sum(inventory_batch.current_stock) < min(inventory_batch.min_stock_threshold)); Planned Partitions = 0; HashAgg Batches = 1; Peak Memory Usage = 193; Disk Usage = 0; Rows Removed by Filter = 994;|
+|SEQ_SCAN (Seq Scan)|table: inventory_batch;|5000|5000|137.0|0.22|0.0|0.005|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Alias = inventory_batch; Plan Width = 24; Actual Loops = 1;|
+#### 功能17优化：统计科室预约量
+```sql
+-- 优化前（复杂嵌套循环）
+SELECT dep.name, COUNT(a.appointment_id) as appointment_count
+FROM department dep
+JOIN doctor d ON dep.department_id = d.department_id
+JOIN schedule s ON d.doctor_id = s.doctor_id
+LEFT JOIN appointment a ON s.schedule_id = a.schedule_id
+WHERE s.work_date = '2024-12-15'
+GROUP BY dep.department_id, dep.name;
+
+-- 优化后（减少JOIN层级，使用子查询）
+SELECT 
+    dep.name,
+    COALESCE(apt_stats.appointment_count, 0) as appointment_count
+FROM department dep
+LEFT JOIN (
+    SELECT 
+        d.department_id,
+        COUNT(a.appointment_id) as appointment_count
+    FROM doctor d
+    JOIN schedule s ON d.doctor_id = s.doctor_id
+    LEFT JOIN appointment a ON s.schedule_id = a.schedule_id
+    WHERE s.work_date = '2024-12-15'
+    GROUP BY d.department_id
+) apt_stats ON dep.department_id = apt_stats.department_id
+ORDER BY dep.name;
+```
+
+|   |   |   |   |   |   |
+|---|---|---|---|---|---|
+|SELECT (select)||||||
+|SORT (sort)||100|702.93|702.68|Parallel Aware = false; Async Capable = false; Plan Width = 226; Sort Key = ["dep.name"];|
+|HASH_JOIN (hash join)||100|699.36|688.08|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Join Type = Left; Plan Width = 226; Inner Unique = true; Hash Cond = (dep.department_id = apt_stats.department_id);|
+|SEQ_SCAN (Seq Scan)|table: department;|100|11.0|0.0|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Alias = dep; Plan Width = 234;|
+|TRANSFORM (Hash)||1|688.07|688.07|Parent Relationship = Inner; Parallel Aware = false; Async Capable = false; Plan Width = 24;|
+|ACCESS (Subquery Scan)||1|688.07|688.04|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Alias = apt_stats; Plan Width = 24;|
+|AGGREGATE (aggregate)||1|688.06|688.04|Strategy = Sorted; Partial Mode = Simple; Parent Relationship = Subquery; Parallel Aware = false; Async Capable = false; Plan Width = 24; Group Key = ["d.department_id"];|
+|SORT (sort)||1|688.05|688.04|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Plan Width = 32; Sort Key = ["d.department_id"];|
+|NESTED_LOOPS (Nested Loop)||1|688.03|0.69|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Join Type = Left; Plan Width = 32; Inner Unique = false;|
+|NESTED_LOOPS (Nested Loop)||1|679.59|0.28|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Join Type = Inner; Plan Width = 32; Inner Unique = true;|
+|SEQ_SCAN (Seq Scan)|table: schedule;|1|671.29|0.0|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Alias = s; Plan Width = 32; Filter = (work_date = '2024-12-15'::date);|
+|INDEX_SCAN (index scan)|table: doctor; index: doctor_pkey;|1|8.29|0.28|Parent Relationship = Inner; Parallel Aware = false; Async Capable = false; Scan Direction = Forward; Alias = d; Plan Width = 32; Index Cond = (doctor_id = s.doctor_id);|
+|INDEX_SCAN (index scan)|table: appointment; index: idx_appointment_schedule_status_time;|1|8.43|0.41|Parent Relationship = Inner; Parallel Aware = false; Async Capable = false; Scan Direction = Forward; Alias = a; Plan Width = 32; Index Cond = (schedule_id = s.schedule_id);|

性能测试/原始SQL测试文件.sql

@@ -0,0 +1,252 @@
+-- ============================================
+-- 原始SQL测试文件
+-- 医院管理系统查询性能测试
+-- 测试环境：PostgreSQL 17，DataGrip 2025.2.5
+-- 数据规模：万级到十万级
+-- ============================================
+
+-- ============================================
+-- 功能01：查询医生排班号源
+-- ============================================
+EXPLAIN (ANALYZE, VERBOSE)
+SELECT schedule_id, slot_no, remaining_appointments
+FROM schedule
+WHERE doctor_id = '550e8400-e29b-41d4-a716-446655440000'
+  AND work_date = '2024-12-15'
+  AND remaining_appointments > 0;
+
+-- ============================================
+-- 功能02：扣减排班号源
+-- ============================================
+EXPLAIN (ANALYZE, VERBOSE)
+UPDATE schedule SET remaining_appointments = remaining_appointments - 1
+WHERE schedule_id = '550e8400-e29b-41d4-a716-446655440001';
+
+-- 回滚以保持数据一致性
+ROLLBACK;
+
+-- ============================================
+-- 功能03：创建预约记录
+-- ============================================
+EXPLAIN (ANALYZE, VERBOSE)
+INSERT INTO appointment (appointment_id, patient_id, schedule_id, appointment_time, status)
+VALUES (gen_random_uuid(), '89c5bb83-c039-4619-b458-7afe7a31fc64',
+        '8510e8ab-37eb-4b12-b69d-f24c076845ca',
+        '2024-12-15 09:30:00', 'scheduled');
+
+-- 回滚以保持数据一致性
+ROLLBACK;
+
+-- ============================================
+-- 功能04：查询医生当日待诊列表
+-- ============================================
+EXPLAIN (ANALYZE, VERBOSE)
+SELECT a.appointment_id, p.name AS patient_name, a.appointment_time
+FROM appointment a
+         JOIN patient p ON a.patient_id = p.patient_id
+         JOIN schedule s ON a.schedule_id = s.schedule_id
+WHERE s.doctor_id = '550e8400-e29b-41d4-a716-446655440004'
+  AND s.work_date = '2024-12-15'
+  AND a.status = 'scheduled'
+ORDER BY a.appointment_time;
+
+-- ============================================
+-- 功能05：更新预约状态为"已签到"
+-- ============================================
+EXPLAIN (ANALYZE, VERBOSE)
+UPDATE appointment SET status = 'checked_in'
+WHERE appointment_id = '550e8400-e29b-41d4-a716-446655440005';
+
+-- 回滚以保持数据一致性
+ROLLBACK;
+
+-- ============================================
+-- 功能06：创建初始病历记录
+-- ============================================
+EXPLAIN (ANALYZE, VERBOSE)
+INSERT INTO medical_record (record_id, patient_id, doctor_id, appointment_id, visit_time)
+VALUES (gen_random_uuid(), '5e8d512a-22c9-4272-9cc7-b5b602b447c6',
+        '51e660c9-8270-439b-b33a-12230b5f27b2',
+        '3221a9b3-05e2-4375-92ce-f395ca05115f',
+        CURRENT_TIMESTAMP);
+
+-- 回滚以保持数据一致性
+ROLLBACK;
+
+-- ============================================
+-- 功能07：更新病历诊断信息
+-- ============================================
+EXPLAIN (ANALYZE, VERBOSE)
+UPDATE medical_record
+SET chief_complaint = '头痛、发热3天',
+    diagnosis_codes = '上呼吸道感染,高血压',
+    updated_at = CURRENT_TIMESTAMP
+WHERE record_id = '550e8400-e29b-41d4-a716-446655440009';
+
+-- 回滚以保持数据一致性
+ROLLBACK;
+
+-- ============================================
+-- 功能08：创建处方主记录
+-- ============================================
+EXPLAIN (ANALYZE, VERBOSE)
+INSERT INTO prescription (prescription_id, record_id, doctor_id, status)
+VALUES ('5fcd0fcb-e522-43fb-b82e-8270c70aeb03', '05e5fe94-6b58-4e08-ae06-fc6990793c29',
+        '0193cd15-f4c4-4331-beaa-01fb67a3d00c', 'pending');
+
+-- 回滚以保持数据一致性
+ROLLBACK;
+
+-- ============================================
+-- 功能09：添加处方明细项
+-- ============================================
+EXPLAIN (ANALYZE, VERBOSE)
+INSERT INTO prescription_item (item_id, prescription_id, drug_id, dosage, frequency, duration_days, quantity)
+VALUES (gen_random_uuid(), '550e8400-e29b-51d4-a716-446655440012',
+        '550e8400-e29b-41d4-a716-446655440013',
+        '1片', '每日3次', 7, 21);
+
+-- 回滚以保持数据一致性
+ROLLBACK;
+
+-- ============================================
+-- 功能10：查询处方明细清单
+-- ============================================
+EXPLAIN (ANALYZE, VERBOSE)
+SELECT d.generic_name, i.dosage, i.frequency, i.quantity
+FROM prescription_item i
+         JOIN drug d ON i.drug_id = d.drug_id
+WHERE i.prescription_id = '550e8400-e29b-41d4-a716-446655440014';
+
+-- ============================================
+-- 功能11：更新处方审核状态
+-- ============================================
+EXPLAIN (ANALYZE, VERBOSE)
+UPDATE prescription SET status = 'approved',
+                        pharmacist_id = '550e8400-e29b-41d4-a716-446655440015',
+                        reviewed_at = CURRENT_TIMESTAMP
+WHERE prescription_id = '550e8400-e29b-41d4-a716-446655440016';
+
+-- 回滚以保持数据一致性
+ROLLBACK;
+
+-- ============================================
+-- 功能12：查询药品库存可用数量
+-- ============================================
+EXPLAIN (ANALYZE, VERBOSE)
+SELECT SUM(current_stock) AS total_stock
+FROM inventory_batch
+WHERE drug_id = '550e8400-e29b-41d4-a716-446655440017';
+
+-- ============================================
+-- 功能13：扣减药品库存
+-- ============================================
+-- 查询符合条件的批次（用于查看执行计划）
+EXPLAIN (ANALYZE, VERBOSE)
+SELECT batch_id FROM inventory_batch
+WHERE drug_id = '550e8400-e29b-41d4-a716-446655440018'
+  AND current_stock >= 10
+ORDER BY expiry_date
+LIMIT 1;
+
+-- ============================================
+-- 功能14：更新处方状态为"已发药"
+-- ============================================
+EXPLAIN (ANALYZE, VERBOSE)
+UPDATE prescription SET status = 'dispensed'
+WHERE prescription_id = '550e8400-e29b-41d4-a716-446655440020';
+
+-- 回滚以保持数据一致性
+ROLLBACK;
+
+-- ============================================
+-- 功能15：取消预约并回退号源
+-- ============================================
+-- 更新预约状态
+EXPLAIN (ANALYZE, VERBOSE)
+UPDATE appointment SET status = 'cancelled', cancelled_at = CURRENT_TIMESTAMP
+WHERE appointment_id = '550e8400-e29b-41d4-a716-446655440021';
+
+-- 回滚以保持数据一致性
+ROLLBACK;
+
+-- 回退号源（子查询版本）
+EXPLAIN (ANALYZE, VERBOSE)
+UPDATE schedule SET remaining_appointments = remaining_appointments + 1
+WHERE schedule_id = (SELECT schedule_id FROM appointment
+                     WHERE appointment_id = '550e8400-e29b-41d4-a716-446655440022');
+
+-- 回滚以保持数据一致性
+ROLLBACK;
+
+-- ============================================
+-- 功能16：查询库存预警药品
+-- ============================================
+EXPLAIN (ANALYZE, VERBOSE)
+SELECT d.generic_name, SUM(ib.current_stock) AS total_stock
+FROM drug d
+         JOIN inventory_batch ib ON d.drug_id = ib.drug_id
+GROUP BY d.drug_id, d.generic_name, ib.min_stock_threshold
+HAVING SUM(ib.current_stock) < ib.min_stock_threshold;
+
+-- ============================================
+-- 功能17：统计科室预约量
+-- ============================================
+EXPLAIN (ANALYZE, VERBOSE)
+SELECT dep.name, COUNT(a.appointment_id) as appointment_count
+FROM department dep
+         JOIN doctor d ON dep.department_id = d.department_id
+         JOIN schedule s ON d.doctor_id = s.doctor_id
+         LEFT JOIN appointment a ON s.schedule_id = a.schedule_id
+WHERE s.work_date = '2024-12-15'
+GROUP BY dep.department_id, dep.name;
+
+-- ============================================
+-- 功能18：统计医生工作量
+-- ============================================
+EXPLAIN (ANALYZE, VERBOSE)
+SELECT d.name, COUNT(mr.record_id) as record_count
+FROM doctor d
+         LEFT JOIN medical_record mr ON d.doctor_id = mr.doctor_id
+    AND EXTRACT(YEAR FROM mr.visit_time) = 2024
+    AND EXTRACT(MONTH FROM mr.visit_time) = 12
+WHERE d.work_status = 'active'
+GROUP BY d.doctor_id, d.name;
+
+-- ============================================
+-- 数据分布统计（基本版）
+-- ============================================
+
+-- 1. 各表数据量统计
+SELECT 'department' as table_name, COUNT(*) as row_count FROM department
+UNION ALL
+SELECT 'doctor', COUNT(*) FROM doctor
+UNION ALL
+SELECT 'patient', COUNT(*) FROM patient
+UNION ALL
+SELECT 'drug', COUNT(*) FROM drug
+UNION ALL
+SELECT 'inventory_batch', COUNT(*) FROM inventory_batch
+UNION ALL
+SELECT 'schedule', COUNT(*) FROM schedule
+UNION ALL
+SELECT 'appointment', COUNT(*) FROM appointment
+UNION ALL
+SELECT 'medical_record', COUNT(*) FROM medical_record
+UNION ALL
+SELECT 'prescription', COUNT(*) FROM prescription
+UNION ALL
+SELECT 'prescription_item', COUNT(*) FROM prescription_item;
+
+-- 2. 现有索引检查
+SELECT
+    t.relname as table_name,
+    i.relname as index_name,
+    a.attname as column_name
+FROM pg_class t
+         JOIN pg_index ix ON t.oid = ix.indrelid
+         JOIN pg_class i ON i.oid = ix.indexrelid
+         JOIN pg_attribute a ON a.attrelid = t.oid AND a.attnum = ANY(ix.indkey)
+WHERE t.relkind = 'r'
+  AND t.relnamespace = (SELECT oid FROM pg_namespace WHERE nspname = 'public')
+ORDER BY t.relname, i.relname;

性能测试/原始SQL测试结果.md

@@ -0,0 +1,469 @@
+```sql
+-- ============================================  
+-- 功能01：查询医生排班号源  
+-- ============================================  
+EXPLAIN (ANALYZE, VERBOSE)  
+SELECT schedule_id, slot_no, remaining_appointments  
+FROM schedule  
+WHERE doctor_id = '550e8400-e29b-41d4-a716-446655440000'  
+  AND work_date = '2024-12-15'  
+  AND remaining_appointments > 0;
+```
+Index Scan using schedule_doctor_id_work_date_slot_no_key on hms.schedule  (cost=0.29..8.31 rows=1 width=22) (actual time=0.042..0.042 rows=0 loops=1)
+"  Output: schedule_id, slot_no, remaining_appointments"
+  Index Cond: ((schedule.doctor_id = '550e8400-e29b-41d4-a716-446655440000'::uuid) AND (schedule.work_date = '2024-12-15'::date))
+  Filter: (schedule.remaining_appointments > 0)
+Planning Time: 0.201 ms
+Execution Time: 0.063 ms
+```sql
+-- ============================================  
+-- 功能02：扣减排班号源  
+-- ============================================
+EXPLAIN (ANALYZE, VERBOSE)  
+UPDATE schedule SET remaining_appointments = remaining_appointments - 1  
+WHERE schedule_id = '550e8400-e29b-41d4-a716-446655440001';
+```
+Update on hms.schedule  (cost=0.29..8.31 rows=0 width=0) (actual time=0.026..0.026 rows=0 loops=1)
+  ->  Index Scan using schedule_pkey on hms.schedule  (cost=0.29..8.31 rows=1 width=10) (actual time=0.018..0.018 rows=0 loops=1)
+"        Output: (remaining_appointments - 1), ctid"
+        Index Cond: (schedule.schedule_id = '550e8400-e29b-41d4-a716-446655440001'::uuid)
+Planning Time: 0.095 ms
+Execution Time: 0.245 ms
+```sql
+-- ============================================  
+-- 功能03：创建预约记录  
+-- ============================================  
+EXPLAIN (ANALYZE, VERBOSE)  
+INSERT INTO appointment (appointment_id, patient_id, schedule_id, appointment_time, status)  
+VALUES (gen_random_uuid(), '89c5bb83-c039-4619-b458-7afe7a31fc64',  
+        '8510e8ab-37eb-4b12-b69d-f24c076845ca',  
+        '2024-12-15 09:30:00', 'scheduled');
+```
+Insert on hms.appointment  (cost=0.00..0.02 rows=0 width=0) (actual time=0.078..0.078 rows=0 loops=1)
+  ->  Result  (cost=0.00..0.02 rows=1 width=704) (actual time=0.018..0.018 rows=1 loops=1)
+"        Output: gen_random_uuid(), '89c5bb83-c039-4619-b458-7afe7a31fc64'::uuid, '8510e8ab-37eb-4b12-b69d-f24c076845ca'::uuid, '2024-12-15 09:30:00'::timestamp without time zone, 'scheduled'::character varying(20), 'online'::character varying(20), CURRENT_TIMESTAMP, NULL::timestamp without time zone, NULL::character varying(255)"
+Planning Time: 0.022 ms
+Trigger RI_ConstraintTrigger_c_27573 for constraint fk_apt_patient: time=0.082 calls=1
+Trigger RI_ConstraintTrigger_c_27578 for constraint fk_apt_schedule: time=0.044 calls=1
+Execution Time: 0.215 ms
+```sql
+-- ============================================  
+-- 功能04：查询医生当日待诊列表  
+-- ============================================  
+EXPLAIN (ANALYZE, VERBOSE)  
+SELECT a.appointment_id, p.name AS patient_name, a.appointment_time  
+FROM appointment a  
+         JOIN patient p ON a.patient_id = p.patient_id  
+         JOIN schedule s ON a.schedule_id = s.schedule_id  
+WHERE s.doctor_id = '550e8400-e29b-41d4-a716-446655440004'  
+  AND s.work_date = '2024-12-15'  
+  AND a.status = 'scheduled'  
+ORDER BY a.appointment_time;
+```
+Sort  (cost=731.51..731.52 rows=1 width=32) (actual time=0.087..0.090 rows=0 loops=1)
+"  Output: a.appointment_id, p.name, a.appointment_time"
+  Sort Key: a.appointment_time
+  Sort Method: quicksort  Memory: 25kB
+  ->  Nested Loop  (cost=8.60..731.50 rows=1 width=32) (actual time=0.053..0.055 rows=0 loops=1)
+"        Output: a.appointment_id, p.name, a.appointment_time"
+        Inner Unique: true
+        ->  Hash Join  (cost=8.32..731.09 rows=1 width=40) (actual time=0.052..0.054 rows=0 loops=1)
+"              Output: a.appointment_id, a.appointment_time, a.patient_id"
+              Inner Unique: true
+              Hash Cond: (a.schedule_id = s.schedule_id)
+              ->  Seq Scan on hms.appointment a  (cost=0.00..696.50 rows=10008 width=56) (actual time=0.028..0.028 rows=1 loops=1)
+"                    Output: a.appointment_id, a.patient_id, a.schedule_id, a.appointment_time, a.status, a.booking_channel, a.created_at, a.cancelled_at, a.cancel_reason"
+                    Filter: ((a.status)::text = 'scheduled'::text)
+                    Rows Removed by Filter: 4
+              ->  Hash  (cost=8.31..8.31 rows=1 width=16) (actual time=0.014..0.015 rows=0 loops=1)
+                    Output: s.schedule_id
+                    Buckets: 1024  Batches: 1  Memory Usage: 8kB
+                    ->  Index Scan using schedule_doctor_id_work_date_slot_no_key on hms.schedule s  (cost=0.29..8.31 rows=1 width=16) (actual time=0.014..0.014 rows=0 loops=1)
+                          Output: s.schedule_id
+                          Index Cond: ((s.doctor_id = '550e8400-e29b-41d4-a716-446655440004'::uuid) AND (s.work_date = '2024-12-15'::date))
+        ->  Index Scan using patient_pkey on hms.patient p  (cost=0.29..0.41 rows=1 width=24) (never executed)
+"              Output: p.patient_id, p.name, p.id_number, p.mobile, p.email, p.gender, p.birth_date, p.address, p.status, p.created_at, p.updated_at"
+              Index Cond: (p.patient_id = a.patient_id)
+Planning Time: 1.273 ms
+Execution Time: 0.119 ms
+```sql
+-- ============================================  
+-- 功能05：更新预约状态为"已签到"  
+-- ============================================  
+EXPLAIN (ANALYZE, VERBOSE)  
+UPDATE appointment SET status = 'checked_in'  
+WHERE appointment_id = '550e8400-e29b-41d4-a716-446655440005';
+```
+Update on hms.appointment  (cost=0.29..8.30 rows=0 width=0) (actual time=0.016..0.016 rows=0 loops=1)
+  ->  Index Scan using appointment_pkey on hms.appointment  (cost=0.29..8.30 rows=1 width=64) (actual time=0.015..0.015 rows=0 loops=1)
+"        Output: 'checked_in'::character varying(20), ctid"
+        Index Cond: (appointment.appointment_id = '550e8400-e29b-41d4-a716-446655440005'::uuid)
+Planning Time: 0.079 ms
+Execution Time: 0.061 ms
+```sql
+-- ============================================  
+-- 功能06：创建初始病历记录  
+-- ============================================  
+EXPLAIN (ANALYZE, VERBOSE)  
+INSERT INTO medical_record (record_id, patient_id, doctor_id, appointment_id, visit_time)  
+VALUES (gen_random_uuid(), '5e8d512a-22c9-4272-9cc7-b5b602b447c6',  
+        '51e660c9-8270-439b-b33a-12230b5f27b2',  
+        '3221a9b3-05e2-4375-92ce-f395ca05115f',  
+        CURRENT_TIMESTAMP);
+```
+Insert on hms.medical_record  (cost=0.00..0.03 rows=0 width=0) (actual time=0.068..0.069 rows=0 loops=1)
+  ->  Result  (cost=0.00..0.03 rows=1 width=1312) (actual time=0.024..0.024 rows=1 loops=1)
+"        Output: gen_random_uuid(), '5e8d512a-22c9-4272-9cc7-b5b602b447c6'::uuid, '51e660c9-8270-439b-b33a-12230b5f27b2'::uuid, '3221a9b3-05e2-4375-92ce-f395ca05115f'::uuid, CURRENT_TIMESTAMP, NULL::text, NULL::text, NULL::text, NULL::character varying(255), NULL::character varying(255), NULL::text, NULL::text, NULL::text, CURRENT_TIMESTAMP, CURRENT_TIMESTAMP"
+Planning Time: 0.023 ms
+Trigger RI_ConstraintTrigger_c_27594 for constraint fk_record_patient: time=0.112 calls=1
+Trigger RI_ConstraintTrigger_c_27599 for constraint fk_record_doctor: time=0.056 calls=1
+Trigger RI_ConstraintTrigger_c_27604 for constraint fk_record_appointment: time=0.558 calls=1
+Execution Time: 0.813 ms
+```sql
+-- ============================================  
+-- 功能07：更新病历诊断信息  
+-- ============================================  
+EXPLAIN (ANALYZE, VERBOSE)  
+UPDATE medical_record  
+SET chief_complaint = '头痛、发热3天',  
+    diagnosis_codes = '上呼吸道感染,高血压',  
+    updated_at = CURRENT_TIMESTAMP  
+WHERE record_id = '550e8400-e29b-41d4-a716-446655440009';
+```
+Update on hms.medical_record  (cost=0.29..8.31 rows=0 width=0) (actual time=0.022..0.022 rows=0 loops=1)
+  ->  Index Scan using medical_record_pkey on hms.medical_record  (cost=0.29..8.31 rows=1 width=562) (actual time=0.020..0.020 rows=0 loops=1)
+"        Output: '头痛、发热3天'::text, '上呼吸道感染,高血压'::character varying(255), CURRENT_TIMESTAMP, ctid"
+        Index Cond: (medical_record.record_id = '550e8400-e29b-41d4-a716-446655440009'::uuid)
+Planning Time: 0.064 ms
+Execution Time: 0.056 ms
+```sql
+-- ============================================  
+-- 功能08：创建处方主记录  
+-- ============================================  
+EXPLAIN (ANALYZE, VERBOSE)  
+INSERT INTO prescription (prescription_id, record_id, doctor_id, status)  
+VALUES ('5fcd0fcb-e522-43fb-b82e-8270c70aeb03', '05e5fe94-6b58-4e08-ae06-fc6990793c29',  
+        '0193cd15-f4c4-4331-beaa-01fb67a3d00c', 'pending');
+```
+Insert on hms.prescription  (cost=0.00..0.01 rows=0 width=0) (actual time=1.102..1.102 rows=0 loops=1)
+  ->  Result  (cost=0.00..0.01 rows=1 width=138) (actual time=0.002..0.003 rows=1 loops=1)
+"        Output: '5fcd0fcb-e522-43fb-b82e-8270c70aeb03'::uuid, '05e5fe94-6b58-4e08-ae06-fc6990793c29'::uuid, '0193cd15-f4c4-4331-beaa-01fb67a3d00c'::uuid, CURRENT_TIMESTAMP, 'pending'::character varying(20), NULL::uuid, NULL::timestamp without time zone"
+Planning Time: 0.020 ms
+Trigger RI_ConstraintTrigger_c_27620 for constraint fk_prescription_record: time=0.083 calls=1
+Trigger RI_ConstraintTrigger_c_27625 for constraint fk_prescription_doctor: time=0.094 calls=1
+Execution Time: 1.288 ms
+```sql
+-- ============================================  
+-- 功能09：添加处方明细项  
+-- ============================================  
+EXPLAIN (ANALYZE, VERBOSE)  
+INSERT INTO prescription_item (item_id, prescription_id, drug_id, dosage, frequency, duration_days, quantity)  
+VALUES (gen_random_uuid(), '550e8400-e29b-51d4-a716-446655440012',  
+        '550e8400-e29b-41d4-a716-446655440013',  
+        '1片', '每日3次', 7, 21);
+```
+Insert on hms.prescription_item  (cost=0.00..0.01 rows=0 width=0) (actual time=0.087..0.088 rows=0 loops=1)
+  ->  Result  (cost=0.00..0.01 rows=1 width=356) (actual time=0.019..0.019 rows=1 loops=1)
+"        Output: gen_random_uuid(), '550e8400-e29b-51d4-a716-446655440012'::uuid, '550e8400-e29b-41d4-a716-446655440013'::uuid, '1片'::character varying(50), '每日3次'::character varying(50), 7, 21, NULL::text, NULL::numeric(10,2), NULL::numeric(10,2)"
+Planning Time: 0.025 ms
+Execution Time: 0.102 ms
+```sql
+-- ============================================  
+-- 功能10：查询处方明细清单  
+-- ============================================
+EXPLAIN (ANALYZE, VERBOSE)  
+SELECT d.generic_name, i.dosage, i.frequency, i.quantity  
+FROM prescription_item i  
+         JOIN drug d ON i.drug_id = d.drug_id  
+WHERE i.prescription_id = '550e8400-e29b-41d4-a716-446655440014';
+```
+Nested Loop  (cost=4.71..40.80 rows=3 width=30) (actual time=0.358..0.358 rows=0 loops=1)
+"  Output: d.generic_name, i.dosage, i.frequency, i.quantity"
+  Inner Unique: true
+  ->  Bitmap Heap Scan on hms.prescription_item i  (cost=4.44..15.91 rows=3 width=37) (actual time=0.357..0.357 rows=0 loops=1)
+"        Output: i.item_id, i.prescription_id, i.drug_id, i.dosage, i.frequency, i.duration_days, i.quantity, i.instructions, i.price, i.amount"
+        Recheck Cond: (i.prescription_id = '550e8400-e29b-41d4-a716-446655440014'::uuid)
+        ->  Bitmap Index Scan on prescription_item_prescription_id_drug_id_key  (cost=0.00..4.44 rows=3 width=0) (actual time=0.339..0.339 rows=0 loops=1)
+              Index Cond: (i.prescription_id = '550e8400-e29b-41d4-a716-446655440014'::uuid)
+  ->  Index Scan using drug_pkey on hms.drug d  (cost=0.28..8.29 rows=1 width=25) (never executed)
+"        Output: d.drug_id, d.generic_name, d.trade_name, d.specification, d.unit, d.dosage_form, d.manufacturer, d.approval_no, d.is_prescription, d.shelf_life_days, d.storage_conditions, d.created_at"
+        Index Cond: (d.drug_id = i.drug_id)
+Planning Time: 0.342 ms
+Execution Time: 0.376 ms
+```sql
+-- ============================================  
+-- 功能11：更新处方审核状态  
+-- ============================================
+EXPLAIN (ANALYZE, VERBOSE)  
+UPDATE prescription SET status = 'approved',  
+                        pharmacist_id = '550e8400-e29b-41d4-a716-446655440015',  
+                        reviewed_at = CURRENT_TIMESTAMP  
+WHERE prescription_id = '550e8400-e29b-41d4-a716-446655440016';
+```
+Update on hms.prescription  (cost=0.29..8.31 rows=0 width=0) (actual time=0.015..0.015 rows=0 loops=1)
+  ->  Index Scan using prescription_pkey on hms.prescription  (cost=0.29..8.31 rows=1 width=88) (actual time=0.014..0.014 rows=0 loops=1)
+"        Output: 'approved'::character varying(20), '550e8400-e29b-41d4-a716-446655440015'::uuid, CURRENT_TIMESTAMP, ctid"
+        Index Cond: (prescription.prescription_id = '550e8400-e29b-41d4-a716-446655440016'::uuid)
+Planning Time: 0.075 ms
+Execution Time: 0.042 ms
+```sql
+-- ============================================  
+-- 功能12：查询药品库存可用数量  
+-- ============================================  
+EXPLAIN (ANALYZE, VERBOSE)  
+SELECT SUM(current_stock) AS total_stock  
+FROM inventory_batch  
+WHERE drug_id = '550e8400-e29b-41d4-a716-446655440017';
+```
+Aggregate  (cost=149.51..149.52 rows=1 width=8) (actual time=0.500..0.500 rows=1 loops=1)
+  Output: sum(current_stock)
+  ->  Seq Scan on hms.inventory_batch  (cost=0.00..149.50 rows=5 width=4) (actual time=0.494..0.494 rows=0 loops=1)
+"        Output: batch_id, drug_id, batch_no, production_date, expiry_date, purchase_quantity, purchase_price, purchase_date, current_stock, department_id, min_stock_threshold, last_stock_in, last_stock_out"
+        Filter: (inventory_batch.drug_id = '550e8400-e29b-41d4-a716-446655440017'::uuid)
+        Rows Removed by Filter: 5000
+Planning Time: 0.131 ms
+Execution Time: 0.515 ms
+```sql
+-- ============================================  
+-- 功能13：扣减药品库存  
+-- ============================================  
+-- 查询符合条件的批次（用于查看执行计划）  
+EXPLAIN (ANALYZE, VERBOSE)  
+SELECT batch_id FROM inventory_batch  
+WHERE drug_id = '550e8400-e29b-41d4-a716-446655440018'  
+  AND current_stock >= 10  
+ORDER BY expiry_date ASC LIMIT 1;
+```
+Limit  (cost=162.03..162.03 rows=1 width=20) (actual time=0.537..0.538 rows=0 loops=1)
+"  Output: batch_id, expiry_date"
+  ->  Sort  (cost=162.03..162.04 rows=5 width=20) (actual time=0.536..0.536 rows=0 loops=1)
+"        Output: batch_id, expiry_date"
+        Sort Key: inventory_batch.expiry_date
+        Sort Method: quicksort  Memory: 25kB
+        ->  Seq Scan on hms.inventory_batch  (cost=0.00..162.00 rows=5 width=20) (actual time=0.525..0.525 rows=0 loops=1)
+"              Output: batch_id, expiry_date"
+              Filter: ((inventory_batch.current_stock >= 10) AND (inventory_batch.drug_id = '550e8400-e29b-41d4-a716-446655440018'::uuid))
+              Rows Removed by Filter: 5000
+Planning Time: 0.127 ms
+Execution Time: 0.550 ms
+```sql
+-- ============================================  
+-- 功能14：更新处方状态为"已发药"  
+-- ============================================  
+EXPLAIN (ANALYZE, VERBOSE)  
+UPDATE prescription SET status = 'dispensed'  
+WHERE prescription_id = '550e8400-e29b-41d4-a716-446655440020';
+```
+Update on hms.prescription  (cost=0.29..8.30 rows=0 width=0) (actual time=0.015..0.015 rows=0 loops=1)
+  ->  Index Scan using prescription_pkey on hms.prescription  (cost=0.29..8.30 rows=1 width=64) (actual time=0.014..0.014 rows=0 loops=1)
+"        Output: 'dispensed'::character varying(20), ctid"
+        Index Cond: (prescription.prescription_id = '550e8400-e29b-41d4-a716-446655440020'::uuid)
+Planning Time: 0.080 ms
+Execution Time: 0.031 ms
+```sql
+-- ============================================  
+-- 功能15：取消预约并回退号源  
+-- ============================================  
+-- 更新预约状态  
+EXPLAIN (ANALYZE, VERBOSE)  
+UPDATE appointment SET status = 'cancelled', cancelled_at = CURRENT_TIMESTAMP  
+WHERE appointment_id = '550e8400-e29b-41d4-a716-446655440021';
+```
+Update on hms.appointment  (cost=0.29..8.31 rows=0 width=0) (actual time=0.014..0.014 rows=0 loops=1)
+  ->  Index Scan using appointment_pkey on hms.appointment  (cost=0.29..8.31 rows=1 width=72) (actual time=0.013..0.013 rows=0 loops=1)
+"        Output: 'cancelled'::character varying(20), CURRENT_TIMESTAMP, ctid"
+        Index Cond: (appointment.appointment_id = '550e8400-e29b-41d4-a716-446655440021'::uuid)
+Planning Time: 0.062 ms
+Execution Time: 0.029 ms
+```sql
+-- 回退号源（子查询版本）  
+EXPLAIN (ANALYZE, VERBOSE)  
+UPDATE schedule SET remaining_appointments = remaining_appointments + 1  
+WHERE schedule_id = (SELECT schedule_id FROM appointment  
+                     WHERE appointment_id = '550e8400-e29b-41d4-a716-446655440022');
+```
+Update on hms.schedule  (cost=8.59..16.61 rows=0 width=0) (actual time=0.019..0.019 rows=0 loops=1)
+  InitPlan 1
+    ->  Index Scan using appointment_pkey on hms.appointment  (cost=0.29..8.30 rows=1 width=16) (actual time=0.007..0.007 rows=0 loops=1)
+          Output: appointment.schedule_id
+          Index Cond: (appointment.appointment_id = '550e8400-e29b-41d4-a716-446655440022'::uuid)
+  ->  Index Scan using schedule_pkey on hms.schedule  (cost=0.29..8.31 rows=1 width=10) (actual time=0.018..0.018 rows=0 loops=1)
+"        Output: (schedule.remaining_appointments + 1), schedule.ctid"
+        Index Cond: (schedule.schedule_id = (InitPlan 1).col1)
+Planning Time: 0.101 ms
+Execution Time: 0.038 ms
+```sql
+-- ============================================  
+-- 功能16：查询库存预警药品  
+-- ============================================  
+EXPLAIN (ANALYZE, VERBOSE)  
+SELECT d.generic_name, SUM(ib.current_stock) AS total_stock  
+FROM drug d  
+         JOIN inventory_batch ib ON d.drug_id = ib.drug_id  
+GROUP BY d.drug_id, d.generic_name, ib.min_stock_threshold  
+HAVING SUM(ib.current_stock) < ib.min_stock_threshold;
+```
+HashAggregate  (cost=234.18..284.18 rows=1333 width=37) (actual time=1.724..1.869 rows=14 loops=1)
+"  Output: d.generic_name, sum(ib.current_stock), d.drug_id, ib.min_stock_threshold"
+"  Group Key: d.drug_id, ib.min_stock_threshold"
+  Filter: (sum(ib.current_stock) < ib.min_stock_threshold)
+  Batches: 1  Memory Usage: 721kB
+  Rows Removed by Filter: 2896
+  ->  Hash Join  (cost=46.50..196.68 rows=5000 width=33) (actual time=0.197..1.071 rows=5000 loops=1)
+"        Output: d.drug_id, ib.min_stock_threshold, d.generic_name, ib.current_stock"
+        Inner Unique: true
+        Hash Cond: (ib.drug_id = d.drug_id)
+        ->  Seq Scan on hms.inventory_batch ib  (cost=0.00..137.00 rows=5000 width=24) (actual time=0.006..0.167 rows=5000 loops=1)
+"              Output: ib.batch_id, ib.drug_id, ib.batch_no, ib.production_date, ib.expiry_date, ib.purchase_quantity, ib.purchase_price, ib.purchase_date, ib.current_stock, ib.department_id, ib.min_stock_threshold, ib.last_stock_in, ib.last_stock_out"
+        ->  Hash  (cost=34.00..34.00 rows=1000 width=25) (actual time=0.185..0.185 rows=1000 loops=1)
+"              Output: d.generic_name, d.drug_id"
+              Buckets: 1024  Batches: 1  Memory Usage: 65kB
+              ->  Seq Scan on hms.drug d  (cost=0.00..34.00 rows=1000 width=25) (actual time=0.006..0.113 rows=1000 loops=1)
+"                    Output: d.generic_name, d.drug_id"
+Planning Time: 0.155 ms
+Execution Time: 1.989 ms
+```sql
+-- ============================================  
+-- 功能17：统计科室预约量  
+-- ============================================  
+EXPLAIN (ANALYZE, VERBOSE)  
+SELECT dep.name, COUNT(a.appointment_id) as appointment_count  
+FROM department dep  
+         JOIN doctor d ON dep.department_id = d.department_id  
+         JOIN schedule s ON d.doctor_id = s.doctor_id  
+         LEFT JOIN appointment a ON s.schedule_id = a.schedule_id  
+WHERE s.work_date = '2024-12-15'  
+GROUP BY dep.department_id, dep.name;
+```
+GroupAggregate  (cost=1379.43..1379.45 rows=1 width=242) (actual time=2.454..2.459 rows=0 loops=1)
+"  Output: dep.name, count(a.appointment_id), dep.department_id"
+  Group Key: dep.department_id
+  ->  Sort  (cost=1379.43..1379.44 rows=1 width=250) (actual time=2.453..2.457 rows=0 loops=1)
+"        Output: dep.department_id, dep.name, a.appointment_id"
+        Sort Key: dep.department_id
+        Sort Method: quicksort  Memory: 25kB
+        ->  Nested Loop  (cost=671.72..1379.42 rows=1 width=250) (actual time=2.436..2.440 rows=0 loops=1)
+"              Output: dep.department_id, dep.name, a.appointment_id"
+              Inner Unique: true
+              ->  Nested Loop  (cost=671.58..1379.24 rows=1 width=32) (actual time=2.436..2.439 rows=0 loops=1)
+"                    Output: d.department_id, a.appointment_id"
+                    Inner Unique: true
+                    ->  Hash Right Join  (cost=671.30..1370.94 rows=1 width=32) (actual time=2.435..2.438 rows=0 loops=1)
+"                          Output: s.doctor_id, a.appointment_id"
+                          Inner Unique: true
+                          Hash Cond: (a.schedule_id = s.schedule_id)
+                          ->  Seq Scan on hms.appointment a  (cost=0.00..634.00 rows=25000 width=32) (never executed)
+"                                Output: a.appointment_id, a.patient_id, a.schedule_id, a.appointment_time, a.status, a.booking_channel, a.created_at, a.cancelled_at, a.cancel_reason"
+                          ->  Hash  (cost=671.29..671.29 rows=1 width=32) (actual time=2.428..2.430 rows=0 loops=1)
+"                                Output: s.doctor_id, s.schedule_id"
+                                Buckets: 1024  Batches: 1  Memory Usage: 8kB
+                                ->  Seq Scan on hms.schedule s  (cost=0.00..671.29 rows=1 width=32) (actual time=2.427..2.427 rows=0 loops=1)
+"                                      Output: s.doctor_id, s.schedule_id"
+                                      Filter: (s.work_date = '2024-12-15'::date)
+                                      Rows Removed by Filter: 27703
+                    ->  Index Scan using doctor_pkey on hms.doctor d  (cost=0.28..8.29 rows=1 width=32) (never executed)
+"                          Output: d.doctor_id, d.department_id, d.name, d.title, d.license_no, d.contact, d.work_status"
+                          Index Cond: (d.doctor_id = s.doctor_id)
+              ->  Index Scan using department_pkey on hms.department dep  (cost=0.14..0.18 rows=1 width=234) (never executed)
+"                    Output: dep.department_id, dep.code, dep.name, dep.location, dep.phone"
+                    Index Cond: (dep.department_id = d.department_id)
+Planning Time: 0.311 ms
+Execution Time: 2.495 ms
+```sql
+-- ============================================  
+-- 功能18：统计医生工作量  
+-- ============================================  
+EXPLAIN (ANALYZE, VERBOSE)  
+SELECT d.name, COUNT(mr.record_id) as record_count  
+FROM doctor d  
+         LEFT JOIN medical_record mr ON d.doctor_id = mr.doctor_id  
+    AND EXTRACT(YEAR FROM mr.visit_time) = 2024  
+    AND EXTRACT(MONTH FROM mr.visit_time) = 12  
+WHERE d.work_status = 'active'  
+GROUP BY d.doctor_id, d.name;
+```
+GroupAggregate  (cost=5247.03..5270.93 rows=1194 width=32) (actual time=13.444..14.002 rows=1194 loops=1)
+"  Output: d.name, count(mr.record_id), d.doctor_id"
+  Group Key: d.doctor_id
+  ->  Merge Left Join  (cost=5247.03..5253.02 rows=1194 width=40) (actual time=13.439..13.643 rows=1295 loops=1)
+"        Output: d.doctor_id, d.name, mr.record_id"
+        Merge Cond: (d.doctor_id = mr.doctor_id)
+        ->  Sort  (cost=114.02..117.01 rows=1194 width=24) (actual time=0.345..0.384 rows=1194 loops=1)
+"              Output: d.name, d.doctor_id"
+              Sort Key: d.doctor_id
+              Sort Method: quicksort  Memory: 98kB
+              ->  Seq Scan on hms.doctor d  (cost=0.00..53.00 rows=1194 width=24) (actual time=0.006..0.200 rows=1194 loops=1)
+"                    Output: d.name, d.doctor_id"
+                    Filter: ((d.work_status)::text = 'active'::text)
+                    Rows Removed by Filter: 806
+        ->  Sort  (cost=5133.01..5133.02 rows=1 width=32) (actual time=13.090..13.111 rows=865 loops=1)
+"              Output: mr.record_id, mr.doctor_id"
+              Sort Key: mr.doctor_id
+              Sort Method: quicksort  Memory: 65kB
+              ->  Seq Scan on hms.medical_record mr  (cost=0.00..5133.00 rows=1 width=32) (actual time=0.016..12.946 rows=865 loops=1)
+"                    Output: mr.record_id, mr.doctor_id"
+                    Filter: ((EXTRACT(year FROM mr.visit_time) = '2024'::numeric) AND (EXTRACT(month FROM mr.visit_time) = '12'::numeric))
+                    Rows Removed by Filter: 19136
+Planning Time: 0.171 ms
+Execution Time: 14.051 ms
+```sql
+-- 1. 各表数据量统计  
+SELECT 'department' as table_name, COUNT(*) as row_count FROM department  
+UNION ALL  
+SELECT 'doctor', COUNT(*) FROM doctor  
+UNION ALL  
+SELECT 'patient', COUNT(*) FROM patient  
+UNION ALL  
+SELECT 'drug', COUNT(*) FROM drug  
+UNION ALL  
+SELECT 'inventory_batch', COUNT(*) FROM inventory_batch  
+UNION ALL  
+SELECT 'schedule', COUNT(*) FROM schedule  
+UNION ALL  
+SELECT 'appointment', COUNT(*) FROM appointment  
+UNION ALL  
+SELECT 'medical_record', COUNT(*) FROM medical_record  
+UNION ALL  
+SELECT 'prescription', COUNT(*) FROM prescription  
+UNION ALL  
+SELECT 'prescription_item', COUNT(*) FROM prescription_item;
+```
+prescription_item,45002
+medical_record,20001
+appointment,25001
+schedule,27703
+prescription,18001
+patient,10000
+inventory_batch,5000
+doctor,2000
+drug,1000
+department,50
+```sql
+-- 2. 现有索引检查（使用系统表）  
+SELECT  
+    t.relname as table_name,  
+    i.relname as index_name,  
+    a.attname as column_name  
+FROM pg_class t  
+         JOIN pg_index ix ON t.oid = ix.indrelid  
+         JOIN pg_class i ON i.oid = ix.indexrelid  
+         JOIN pg_attribute a ON a.attrelid = t.oid AND a.attnum = ANY(ix.indkey)  
+WHERE t.relkind = 'r'  
+  AND t.relnamespace = (SELECT oid FROM pg_namespace WHERE nspname = 'public')  
+ORDER BY t.relname, i.relname;
+```
+无
+#  完整运行结果
+|   |   |   |   |   |   |   |   |   |
+|---|---|---|---|---|---|---|---|---|
+|SELECT (select)||||||||Planning Time = 0.375; Triggers = []; Execution Time = 0.1;|
+|SORT (sort)||3|0|49.36|0.073|49.35|0.072|Parallel Aware = false; Async Capable = false; Plan Width = 192; Actual Loops = 1; Sort Key = ["t.relname","i.relname"]; Sort Method = quicksort; Sort Space Used = 25; Sort Space Type = Memory;|
+|SEQ_SCAN (Seq Scan)|table: pg_namespace;|1|0|1.05|0.004|0.0|0.004|Parent Relationship = InitPlan; Subplan Name = InitPlan 1; Parallel Aware = false; Async Capable = false; Alias = pg_namespace; Plan Width = 4; Actual Loops = 1; Filter = (nspname = 'public'::name); Rows Removed by Filter = 7;|
+|NESTED_LOOPS (Nested Loop)||3|0|48.28|0.067|21.54|0.067|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Join Type = Inner; Plan Width = 192; Actual Loops = 1; Inner Unique = true;|
+|NESTED_LOOPS (Nested Loop)||3|0|46.09|0.067|21.27|0.066|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Join Type = Inner; Plan Width = 132; Actual Loops = 1; Inner Unique = false; Join Filter = (t.oid = a.attrelid); Rows Removed by Join Filter = 0;|
+|HASH_JOIN (hash join)||7|0|28.06|0.067|20.99|0.066|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Join Type = Inner; Plan Width = 103; Actual Loops = 1; Inner Unique = true; Hash Cond = (ix.indrelid = t.oid);|
+|SEQ_SCAN (Seq Scan)|table: pg_index;|164|1|6.64|0.007|0.0|0.007|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Alias = ix; Plan Width = 35; Actual Loops = 1;|
+|TRANSFORM (Hash)||19|0|20.75|0.054|20.75|0.054|Parent Relationship = Inner; Parallel Aware = false; Async Capable = false; Plan Width = 68; Actual Loops = 1; Hash Buckets = 1024; Original Hash Buckets = 1024; Hash Batches = 1; Original Hash Batches = 1; Peak Memory Usage = 8;|
+|SEQ_SCAN (Seq Scan)|table: pg_class;|19|0|20.75|0.054|0.0|0.054|Parent Relationship = Outer; Parallel Aware = false; Async Capable = false; Alias = t; Plan Width = 68; Actual Loops = 1; Filter = ((relkind = 'r'::"char") AND (relnamespace = (InitPlan 1).col1)); Rows Removed by Filter = 454;|
+|INDEX_SCAN (index scan)|table: pg_attribute; index: pg_attribute_relid_attnam_index;|1|0|2.56|0.0|0.28|0.0|Parent Relationship = Inner; Parallel Aware = false; Async Capable = false; Scan Direction = Forward; Alias = a; Plan Width = 70; Actual Loops = 0; Index Cond = (attrelid = ix.indrelid); Rows Removed by Index Recheck = 0; Filter = (attnum = ANY ((ix.indkey)::smallint[])); Rows Removed by Filter = 0;|
+|INDEX_SCAN (index scan)|table: pg_class; index: pg_class_oid_index;|1|0|0.73|0.0|0.27|0.0|Parent Relationship = Inner; Parallel Aware = false; Async Capable = false; Scan Direction = Forward; Alias = i; Plan Width = 68; Actual Loops = 0; Index Cond = (oid = ix.indexrelid); Rows Removed by Index Recheck = 0;|