-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathindex.html
More file actions
1768 lines (1685 loc) · 84.5 KB
/
index.html
File metadata and controls
1768 lines (1685 loc) · 84.5 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
<!DOCTYPE html>
<html lang="zh-CN">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>MySQL SQL 练习笔记：商城数据表实战</title>
<style>
:root {
--bg: #f3f6fb;
--card: #ffffff;
--text: #172033;
--muted: #69758a;
--border: #e5eaf2;
--primary: #2563eb;
--primary-soft: #eaf1ff;
--code-bg: #101827;
--code-text: #e7eefc;
--shadow: 0 16px 40px rgba(15, 23, 42, .08);
--radius: 18px;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
margin: 0;
background: radial-gradient(circle at top left, #eaf1ff 0, transparent 34%), var(--bg);
color: var(--text);
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", Arial, sans-serif;
line-height: 1.6;
}
a { color: inherit; text-decoration: none; }
.page { max-width: 1180px; margin: 0 auto; padding: 28px 20px 70px; }
.hero {
display: grid;
grid-template-columns: minmax(0, 1fr) 330px;
gap: 18px;
align-items: stretch;
margin-bottom: 18px;
}
.hero-main, .hero-side, .content-card {
background: rgba(255,255,255,.9);
border: 1px solid var(--border);
border-radius: var(--radius);
box-shadow: var(--shadow);
}
.hero-main { padding: 28px; }
.hero-main h1 { margin: 0 0 10px; font-size: 32px; line-height: 1.2; }
.hero-main p { margin: 0; color: var(--muted); font-size: 15px; }
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 18px; }
.chip {
padding: 7px 10px;
border-radius: 999px;
background: var(--primary-soft);
color: #1d4ed8;
font-size: 12px;
font-weight: 700;
}
.hero-side { padding: 20px; display: grid; gap: 12px; align-content: center; }
.stat { padding: 14px; border-radius: 14px; background: #f8fbff; border: 1px solid var(--border); }
.stat strong { font-size: 22px; padding-right: 6px; }
.stat span { color: var(--muted); font-size: 13px; }
.layout { display: grid; grid-template-columns: 260px minmax(0, 1fr); gap: 18px; align-items: start; }
.sidebar { position: sticky; top: 18px; display: grid; gap: 12px; }
.content-card { padding: 16px; }
.content-card h2 { margin: 0 0 12px; font-size: 16px; }
.nav { display: grid; gap: 6px; max-height: calc(100vh - 220px); overflow: auto; padding-right: 4px; }
.nav a { padding: 9px 10px; border-radius: 10px; color: var(--muted); font-size: 13px; }
.nav a:hover { background: var(--primary-soft); color: var(--primary); }
.search-input { width: 100%; border: 1px solid var(--border); border-radius: 12px; padding: 12px 13px; outline: none; font-size: 14px; }
.search-input:focus { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(37,99,235,.12); }
.main { display: grid; gap: 16px; }
.section-title { margin: 16px 0 0; padding: 20px 4px 4px; }
.section-title p { margin: 0 0 4px; color: var(--primary); font-size: 12px; font-weight: 800; text-transform: uppercase; letter-spacing: .08em; }
.section-title h2 { margin: 0; font-size: 22px; }
.sql-card {
background: var(--card);
border: 1px solid var(--border);
border-radius: var(--radius);
box-shadow: var(--shadow);
overflow: hidden;
}
.card-head {
display: flex;
justify-content: space-between;
gap: 16px;
padding: 20px 20px 14px;
border-bottom: 1px solid var(--border);
}
.badge { display: inline-flex; align-items:center; padding: 4px 9px; border-radius: 999px; background: var(--primary-soft); color: var(--primary); font-size: 12px; font-weight: 800; }
.card-head h3 { margin: 10px 0 0; font-size: 20px; }
.desc { margin: 7px 0 0; color: var(--muted); font-size: 14px; }
.copy-btn {
flex: 0 0 auto;
height: 36px;
padding: 0 13px;
border: 0;
border-radius: 10px;
background: var(--text);
color: #fff;
font-weight: 700;
cursor: pointer;
}
.copy-btn:hover { opacity: .88; }
pre { margin: 0; padding: 18px 20px; overflow: auto; background: var(--code-bg); color: var(--code-text); font-size: 13px; line-height: 1.65; }
code { font-family: Consolas, Monaco, "Courier New", monospace; }
.screenshot { margin: 0; padding: 18px 20px 20px; background: #fbfdff; }
.shot-placeholder {
min-height: 180px;
border: 1px dashed #b9c6dc;
border-radius: 14px;
background: repeating-linear-gradient(45deg, #f5f8fc, #f5f8fc 10px, #eef3fb 10px, #eef3fb 20px);
display: flex;
align-items: center;
justify-content: center;
flex-direction: column;
gap: 8px;
color: var(--muted);
text-align: center;
padding: 18px;
}
.shot-placeholder strong { color: var(--text); }
.shot-placeholder span { font-family: Consolas, Monaco, "Courier New", monospace; font-size: 13px; }
.screenshot img { display: block; max-width: 100%; border-radius: 14px; border: 1px solid var(--border); }
figcaption { margin-top: 10px; color: var(--muted); font-size: 13px; }
.exercise-list { padding: 20px 24px 24px; }
.exercise-list li { margin: 8px 0; }
.footer-note { color: var(--muted); font-size: 13px; padding: 16px 4px; }
mark { background: #fef3c7; color: inherit; padding: 0 2px; border-radius: 3px; }
@media (max-width: 980px) {
.hero { grid-template-columns: 1fr; }
.layout { grid-template-columns: 1fr; }
.sidebar { position: static; }
.nav { max-height: none; grid-template-columns: repeat(auto-fit, minmax(160px, 1fr)); }
}
@media (max-width: 620px) {
.page { padding: 16px 12px 46px; }
.hero-main { padding: 22px; }
.hero-main h1 { font-size: 25px; }
.card-head { flex-direction: column; }
.copy-btn { width: 100%; }
pre { font-size: 12px; padding: 15px; }
.screenshot { padding: 15px; }
}
</style>
</head>
<body>
<div class="page">
<header class="hero">
<div class="hero-main">
<h1>MySQL SQL 练习笔记：商城数据表实战</h1>
<p>一套基于简单商城业务场景的 MySQL SQL 练习资料，包含建库建表、测试数据、查询、聚合、JOIN、子查询、事务、视图和运行结果截图记录。</p>
<div class="chips">
<span class="chip">MySQL</span>
<span class="chip">SELECT / JOIN / GROUP BY</span>
<span class="chip">事务 / 视图 / 索引</span>
<span class="chip">运行截图记录</span>
</div>
</div>
<aside class="hero-side">
<div class="stat"><strong>60</strong><span>个 SQL 练习块</span></div>
<div class="stat"><strong>4</strong><span>张模拟业务表</span></div>
<div class="stat"><strong>10</strong><span>道自测题</span></div>
</aside>
</header>
<div class="layout">
<aside class="sidebar">
<div class="content-card">
<h2>快速搜索</h2>
<input id="search" class="search-input" type="search" placeholder="搜索 SELECT、JOIN、客户、订单..." />
</div>
<div class="content-card">
<h2>练习目录</h2>
<nav class="nav">
<a href="#section-01">第 1 部分 · 创建练习数据库</a><a href="#section-02">第 2 部分 · 创建数据表</a><a href="#section-03">第 3 部分 · 插入测试数据</a><a href="#section-04">第 4 部分 · 基础查询 SELECT</a><a href="#section-05">第 5 部分 · 条件查询 WHERE</a><a href="#section-06">第 6 部分 · 排序 ORDER BY</a><a href="#section-07">第 7 部分 · 聚合函数 COUNT / SUM / AVG / MAX / MIN</a><a href="#section-08">第 8 部分 · 分组 GROUP BY</a><a href="#section-09">第 9 部分 · HAVING 分组后筛选</a><a href="#section-10">第 10 部分 · 单表 INSERT / UPDATE / DELETE</a><a href="#section-11">第 11 部分 · 连接查询 JOIN</a><a href="#section-12">第 12 部分 · LEFT JOIN</a><a href="#section-13">第 13 部分 · 子查询 Subquery</a><a href="#section-14">第 14 部分 · CASE WHEN 条件判断</a><a href="#section-15">第 15 部分 · 日期函数</a><a href="#section-16">第 16 部分 · 常用业务查询综合练习</a><a href="#section-17">第 17 部分 · 索引练习</a><a href="#section-18">第 18 部分 · 事务练习 Transaction</a><a href="#section-19">第 19 部分 · 视图 View</a>
<a href="#section-20">第 20 部分 · 自己练习题</a>
</nav>
</div>
</aside>
<main class="main">
<section class="content-card">
<h2>使用说明</h2>
<p>先在 MySQL 中执行第 1-3 部分完成初始化，然后按编号逐条执行 SQL。每条 SQL 执行后，把截图保存到对应路径，例如 <code>docs/screenshots/04-01.png</code>，上传到 GitHub 后本页面会自动显示截图。</p>
</section>
<section class="section-title" id="section-01">
<p>Section 01</p>
<h2>第 1 部分：创建练习数据库</h2>
</section><article class="sql-card" id="sql-01-01" data-title="1.1 创建练习数据库" data-section="1" data-tag="初始化">
<div class="card-head">
<div>
<span class="badge">1.1</span>
<h3>创建练习数据库</h3>
<p class="desc">创建并切换到练习数据库。</p>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">DROP DATABASE IF EXISTS sql_practice_shop;
CREATE DATABASE sql_practice_shop
DEFAULT CHARACTER SET utf8mb4
DEFAULT COLLATE utf8mb4_unicode_ci;
USE sql_practice_shop;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/01-01.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/01-01.png</span>
</div>
<img src="docs/screenshots/01-01.png" alt="1.1 创建练习数据库 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/01-01.png</code></figcaption>
</figure>
</article><section class="section-title" id="section-02">
<p>Section 02</p>
<h2>第 2 部分：创建数据表</h2>
</section><article class="sql-card" id="sql-02-01" data-title="2.1 创建数据表" data-section="2" data-tag="初始化">
<div class="card-head">
<div>
<span class="badge">2.1</span>
<h3>创建数据表</h3>
<p class="desc">创建 customers、products、orders、order_items 四张练习表。</p>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">-- 业务场景：一个简单商城
-- customers 客户表
-- products 产品表
-- orders 订单表
-- order_items 订单明细表
DROP TABLE IF EXISTS order_items;
DROP TABLE IF EXISTS orders;
DROP TABLE IF EXISTS products;
DROP TABLE IF EXISTS customers;
CREATE TABLE customers (
id INT AUTO_INCREMENT PRIMARY KEY,
name VARCHAR(100) NOT NULL,
city VARCHAR(80) NOT NULL,
email VARCHAR(160) NOT NULL UNIQUE,
level ENUM('normal', 'vip') NOT NULL DEFAULT 'normal',
created_at DATE NOT NULL
) ENGINE=InnoDB;
CREATE TABLE products (
id INT AUTO_INCREMENT PRIMARY KEY,
name VARCHAR(120) NOT NULL,
category VARCHAR(80) NOT NULL,
price DECIMAL(10, 2) NOT NULL,
stock INT NOT NULL DEFAULT 0,
status ENUM('active', 'inactive') NOT NULL DEFAULT 'active'
) ENGINE=InnoDB;
CREATE TABLE orders (
id INT AUTO_INCREMENT PRIMARY KEY,
customer_id INT NOT NULL,
order_no VARCHAR(40) NOT NULL UNIQUE,
status ENUM('pending', 'paid', 'shipped', 'cancelled') NOT NULL DEFAULT 'pending',
order_date DATE NOT NULL,
note VARCHAR(255),
CONSTRAINT fk_orders_customer
FOREIGN KEY (customer_id) REFERENCES customers(id)
ON UPDATE CASCADE
ON DELETE RESTRICT
) ENGINE=InnoDB;
CREATE TABLE order_items (
id INT AUTO_INCREMENT PRIMARY KEY,
order_id INT NOT NULL,
product_id INT NOT NULL,
quantity INT NOT NULL,
unit_price DECIMAL(10, 2) NOT NULL,
CONSTRAINT fk_order_items_order
FOREIGN KEY (order_id) REFERENCES orders(id)
ON UPDATE CASCADE
ON DELETE CASCADE,
CONSTRAINT fk_order_items_product
FOREIGN KEY (product_id) REFERENCES products(id)
ON UPDATE CASCADE
ON DELETE RESTRICT
) ENGINE=InnoDB;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/02-01.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/02-01.png</span>
</div>
<img src="docs/screenshots/02-01.png" alt="2.1 创建数据表 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/02-01.png</code></figcaption>
</figure>
</article><section class="section-title" id="section-03">
<p>Section 03</p>
<h2>第 3 部分：插入测试数据</h2>
</section><article class="sql-card" id="sql-03-01" data-title="3.1 插入测试数据" data-section="3" data-tag="初始化">
<div class="card-head">
<div>
<span class="badge">3.1</span>
<h3>插入测试数据</h3>
<p class="desc">插入一批商城测试数据，后续 SELECT / JOIN / GROUP BY 都基于这些数据。</p>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">INSERT INTO customers (name, city, email, level, created_at) VALUES
('Alice Wang', 'Toronto', 'alice@example.com', 'vip', '2024-01-10'),
('Bob Chen', 'Vancouver', 'bob@example.com', 'normal', '2024-02-15'),
('Cindy Li', 'Montreal', 'cindy@example.com', 'vip', '2024-03-20'),
('David Zhang', 'Calgary', 'david@example.com', 'normal', '2024-04-05'),
('Eva Liu', 'Toronto', 'eva@example.com', 'normal', '2024-04-18'),
('Frank Sun', 'Ottawa', 'frank@example.com', 'vip', '2024-05-01');
INSERT INTO products (name, category, price, stock, status) VALUES
('Composite Decking Board', 'Decking', 29.90, 500, 'active'),
('Decking Starter Clip', 'Accessories', 0.45, 3000, 'active'),
('Decking Joist', 'Substructure', 12.50, 800, 'active'),
('Wall Cladding Panel', 'Cladding', 35.80, 260, 'active'),
('Corner Trim', 'Accessories', 8.90, 600, 'active'),
('Old Sample Board', 'Sample', 3.00, 0, 'inactive'),
('Fascia Board', 'Decking', 18.60, 180, 'active'),
('Screw Pack', 'Accessories', 6.50, 1200, 'active');
INSERT INTO orders (customer_id, order_no, status, order_date, note) VALUES
(1, 'SO20240501001', 'paid', '2024-05-01', 'VIP customer'),
(2, 'SO20240503001', 'pending', '2024-05-03', NULL),
(3, 'SO20240505001', 'shipped', '2024-05-05', 'Urgent delivery'),
(1, 'SO20240510001', 'cancelled', '2024-05-10', 'Customer changed plan'),
(5, 'SO20240512001', 'paid', '2024-05-12', NULL),
(6, 'SO20240515001', 'paid', '2024-05-15', 'Repeat customer'),
(4, 'SO20240518001', 'shipped', '2024-05-18', NULL),
(3, 'SO20240520001', 'paid', '2024-05-20', NULL);
INSERT INTO order_items (order_id, product_id, quantity, unit_price) VALUES
(1, 1, 20, 29.90),
(1, 2, 200, 0.45),
(1, 8, 5, 6.50),
(2, 4, 10, 35.80),
(2, 5, 8, 8.90),
(3, 1, 30, 29.90),
(3, 3, 12, 12.50),
(3, 2, 300, 0.45),
(4, 6, 5, 3.00),
(5, 7, 15, 18.60),
(5, 8, 3, 6.50),
(6, 4, 12, 35.80),
(6, 5, 10, 8.90),
(6, 8, 2, 6.50),
(7, 1, 25, 29.90),
(7, 3, 10, 12.50),
(8, 1, 10, 29.90),
(8, 4, 6, 35.80),
(8, 5, 4, 8.90);</code></pre>
<figure class="screenshot" data-path="docs/screenshots/03-01.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/03-01.png</span>
</div>
<img src="docs/screenshots/03-01.png" alt="3.1 插入测试数据 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/03-01.png</code></figcaption>
</figure>
</article><section class="section-title" id="section-04">
<p>Section 04</p>
<h2>第 4 部分：基础查询 SELECT</h2>
</section><article class="sql-card" id="sql-04-01" data-title="4.1 查看所有客户" data-section="4" data-tag="基础查询 SELECT">
<div class="card-head">
<div>
<span class="badge">4.1</span>
<h3>查看所有客户</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT *
FROM customers;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/04-01.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/04-01.png</span>
</div>
<img src="docs/screenshots/04-01.png" alt="4.1 查看所有客户 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/04-01.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-04-02" data-title="4.2 只查询客户姓名、城市、邮箱" data-section="4" data-tag="基础查询 SELECT">
<div class="card-head">
<div>
<span class="badge">4.2</span>
<h3>只查询客户姓名、城市、邮箱</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT name, city, email
FROM customers;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/04-02.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/04-02.png</span>
</div>
<img src="docs/screenshots/04-02.png" alt="4.2 只查询客户姓名、城市、邮箱 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/04-02.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-04-03" data-title="4.3 查询产品名称、分类、价格，并给字段起别名" data-section="4" data-tag="基础查询 SELECT">
<div class="card-head">
<div>
<span class="badge">4.3</span>
<h3>查询产品名称、分类、价格，并给字段起别名</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT
name AS product_name,
category AS product_category,
price AS unit_price
FROM products;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/04-03.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/04-03.png</span>
</div>
<img src="docs/screenshots/04-03.png" alt="4.3 查询产品名称、分类、价格，并给字段起别名 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/04-03.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-04-04" data-title="4.4 查询前 5 个产品" data-section="4" data-tag="基础查询 SELECT">
<div class="card-head">
<div>
<span class="badge">4.4</span>
<h3>查询前 5 个产品</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT *
FROM products
LIMIT 5;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/04-04.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/04-04.png</span>
</div>
<img src="docs/screenshots/04-04.png" alt="4.4 查询前 5 个产品 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/04-04.png</code></figcaption>
</figure>
</article><section class="section-title" id="section-05">
<p>Section 05</p>
<h2>第 5 部分：条件查询 WHERE</h2>
</section><article class="sql-card" id="sql-05-01" data-title="5.1 查询 Toronto 的客户" data-section="5" data-tag="条件查询 WHERE">
<div class="card-head">
<div>
<span class="badge">5.1</span>
<h3>查询 Toronto 的客户</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT *
FROM customers
WHERE city = 'Toronto';</code></pre>
<figure class="screenshot" data-path="docs/screenshots/05-01.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/05-01.png</span>
</div>
<img src="docs/screenshots/05-01.png" alt="5.1 查询 Toronto 的客户 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/05-01.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-05-02" data-title="5.2 查询 VIP 客户" data-section="5" data-tag="条件查询 WHERE">
<div class="card-head">
<div>
<span class="badge">5.2</span>
<h3>查询 VIP 客户</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT *
FROM customers
WHERE level = 'vip';</code></pre>
<figure class="screenshot" data-path="docs/screenshots/05-02.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/05-02.png</span>
</div>
<img src="docs/screenshots/05-02.png" alt="5.2 查询 VIP 客户 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/05-02.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-05-03" data-title="5.3 查询价格大于 20 的产品" data-section="5" data-tag="条件查询 WHERE">
<div class="card-head">
<div>
<span class="badge">5.3</span>
<h3>查询价格大于 20 的产品</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT *
FROM products
WHERE price > 20;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/05-03.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/05-03.png</span>
</div>
<img src="docs/screenshots/05-03.png" alt="5.3 查询价格大于 20 的产品 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/05-03.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-05-04" data-title="5.4 查询库存大于 0 且状态为 active 的产品" data-section="5" data-tag="条件查询 WHERE">
<div class="card-head">
<div>
<span class="badge">5.4</span>
<h3>查询库存大于 0 且状态为 active 的产品</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT *
FROM products
WHERE stock > 0
AND status = 'active';</code></pre>
<figure class="screenshot" data-path="docs/screenshots/05-04.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/05-04.png</span>
</div>
<img src="docs/screenshots/05-04.png" alt="5.4 查询库存大于 0 且状态为 active 的产品 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/05-04.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-05-05" data-title="5.5 查询 Decking 或 Accessories 分类的产品" data-section="5" data-tag="条件查询 WHERE">
<div class="card-head">
<div>
<span class="badge">5.5</span>
<h3>查询 Decking 或 Accessories 分类的产品</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT *
FROM products
WHERE category IN ('Decking', 'Accessories');</code></pre>
<figure class="screenshot" data-path="docs/screenshots/05-05.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/05-05.png</span>
</div>
<img src="docs/screenshots/05-05.png" alt="5.5 查询 Decking 或 Accessories 分类的产品 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/05-05.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-05-06" data-title="5.6 模糊查询：查询名称中包含 Board 的产品" data-section="5" data-tag="条件查询 WHERE">
<div class="card-head">
<div>
<span class="badge">5.6</span>
<h3>模糊查询：查询名称中包含 Board 的产品</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT *
FROM products
WHERE name LIKE '%Board%';</code></pre>
<figure class="screenshot" data-path="docs/screenshots/05-06.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/05-06.png</span>
</div>
<img src="docs/screenshots/05-06.png" alt="5.6 模糊查询：查询名称中包含 Board 的产品 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/05-06.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-05-07" data-title="5.7 查询 2024-05-10 之后的订单" data-section="5" data-tag="条件查询 WHERE">
<div class="card-head">
<div>
<span class="badge">5.7</span>
<h3>查询 2024-05-10 之后的订单</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT *
FROM orders
WHERE order_date > '2024-05-10';</code></pre>
<figure class="screenshot" data-path="docs/screenshots/05-07.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/05-07.png</span>
</div>
<img src="docs/screenshots/05-07.png" alt="5.7 查询 2024-05-10 之后的订单 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/05-07.png</code></figcaption>
</figure>
</article><section class="section-title" id="section-06">
<p>Section 06</p>
<h2>第 6 部分：排序 ORDER BY</h2>
</section><article class="sql-card" id="sql-06-01" data-title="6.1 产品按价格从低到高排序" data-section="6" data-tag="排序 ORDER BY">
<div class="card-head">
<div>
<span class="badge">6.1</span>
<h3>产品按价格从低到高排序</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT *
FROM products
ORDER BY price ASC;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/06-01.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/06-01.png</span>
</div>
<img src="docs/screenshots/06-01.png" alt="6.1 产品按价格从低到高排序 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/06-01.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-06-02" data-title="6.2 产品按库存从高到低排序" data-section="6" data-tag="排序 ORDER BY">
<div class="card-head">
<div>
<span class="badge">6.2</span>
<h3>产品按库存从高到低排序</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT *
FROM products
ORDER BY stock DESC;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/06-02.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/06-02.png</span>
</div>
<img src="docs/screenshots/06-02.png" alt="6.2 产品按库存从高到低排序 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/06-02.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-06-03" data-title="6.3 订单先按状态排序，再按日期倒序排序" data-section="6" data-tag="排序 ORDER BY">
<div class="card-head">
<div>
<span class="badge">6.3</span>
<h3>订单先按状态排序，再按日期倒序排序</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT *
FROM orders
ORDER BY status ASC, order_date DESC;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/06-03.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/06-03.png</span>
</div>
<img src="docs/screenshots/06-03.png" alt="6.3 订单先按状态排序，再按日期倒序排序 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/06-03.png</code></figcaption>
</figure>
</article><section class="section-title" id="section-07">
<p>Section 07</p>
<h2>第 7 部分：聚合函数 COUNT / SUM / AVG / MAX / MIN</h2>
</section><article class="sql-card" id="sql-07-01" data-title="7.1 统计客户总数" data-section="7" data-tag="聚合函数 COUNT / SUM / AVG / MAX / MIN">
<div class="card-head">
<div>
<span class="badge">7.1</span>
<h3>统计客户总数</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT COUNT(*) AS customer_count
FROM customers;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/07-01.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/07-01.png</span>
</div>
<img src="docs/screenshots/07-01.png" alt="7.1 统计客户总数 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/07-01.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-07-02" data-title="7.2 统计产品平均价格" data-section="7" data-tag="聚合函数 COUNT / SUM / AVG / MAX / MIN">
<div class="card-head">
<div>
<span class="badge">7.2</span>
<h3>统计产品平均价格</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT AVG(price) AS average_price
FROM products;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/07-02.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/07-02.png</span>
</div>
<img src="docs/screenshots/07-02.png" alt="7.2 统计产品平均价格 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/07-02.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-07-03" data-title="7.3 查询最高产品价格和最低产品价格" data-section="7" data-tag="聚合函数 COUNT / SUM / AVG / MAX / MIN">
<div class="card-head">
<div>
<span class="badge">7.3</span>
<h3>查询最高产品价格和最低产品价格</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT
MAX(price) AS max_price,
MIN(price) AS min_price
FROM products;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/07-03.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/07-03.png</span>
</div>
<img src="docs/screenshots/07-03.png" alt="7.3 查询最高产品价格和最低产品价格 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/07-03.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-07-04" data-title="7.4 统计所有产品总库存" data-section="7" data-tag="聚合函数 COUNT / SUM / AVG / MAX / MIN">
<div class="card-head">
<div>
<span class="badge">7.4</span>
<h3>统计所有产品总库存</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT SUM(stock) AS total_stock
FROM products;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/07-04.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/07-04.png</span>
</div>
<img src="docs/screenshots/07-04.png" alt="7.4 统计所有产品总库存 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/07-04.png</code></figcaption>
</figure>
</article><section class="section-title" id="section-08">
<p>Section 08</p>
<h2>第 8 部分：分组 GROUP BY</h2>
</section><article class="sql-card" id="sql-08-01" data-title="8.1 按城市统计客户数量" data-section="8" data-tag="分组 GROUP BY">
<div class="card-head">
<div>
<span class="badge">8.1</span>
<h3>按城市统计客户数量</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT
city,
COUNT(*) AS customer_count
FROM customers
GROUP BY city
ORDER BY customer_count DESC;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/08-01.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/08-01.png</span>
</div>
<img src="docs/screenshots/08-01.png" alt="8.1 按城市统计客户数量 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/08-01.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-08-02" data-title="8.2 按产品分类统计产品数量" data-section="8" data-tag="分组 GROUP BY">
<div class="card-head">
<div>
<span class="badge">8.2</span>
<h3>按产品分类统计产品数量</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT
category,
COUNT(*) AS product_count
FROM products
GROUP BY category
ORDER BY product_count DESC;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/08-02.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/08-02.png</span>
</div>
<img src="docs/screenshots/08-02.png" alt="8.2 按产品分类统计产品数量 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/08-02.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-08-03" data-title="8.3 按订单状态统计订单数量" data-section="8" data-tag="分组 GROUP BY">
<div class="card-head">
<div>
<span class="badge">8.3</span>
<h3>按订单状态统计订单数量</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT
status,
COUNT(*) AS order_count
FROM orders
GROUP BY status;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/08-03.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/08-03.png</span>
</div>
<img src="docs/screenshots/08-03.png" alt="8.3 按订单状态统计订单数量 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/08-03.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-08-04" data-title="8.4 按产品分类统计平均价格" data-section="8" data-tag="分组 GROUP BY">
<div class="card-head">
<div>
<span class="badge">8.4</span>
<h3>按产品分类统计平均价格</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT
category,
AVG(price) AS average_price
FROM products
GROUP BY category
ORDER BY average_price DESC;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/08-04.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/08-04.png</span>
</div>
<img src="docs/screenshots/08-04.png" alt="8.4 按产品分类统计平均价格 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/08-04.png</code></figcaption>
</figure>
</article><section class="section-title" id="section-09">
<p>Section 09</p>
<h2>第 9 部分：HAVING 分组后筛选</h2>
</section><article class="sql-card" id="sql-09-01" data-title="9.1 查询客户数量大于 1 的城市" data-section="9" data-tag="HAVING 分组后筛选">
<div class="card-head">
<div>
<span class="badge">9.1</span>
<h3>查询客户数量大于 1 的城市</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT
city,
COUNT(*) AS customer_count
FROM customers
GROUP BY city
HAVING COUNT(*) > 1;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/09-01.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/09-01.png</span>
</div>
<img src="docs/screenshots/09-01.png" alt="9.1 查询客户数量大于 1 的城市 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/09-01.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-09-02" data-title="9.2 查询平均价格大于 10 的产品分类" data-section="9" data-tag="HAVING 分组后筛选">
<div class="card-head">
<div>
<span class="badge">9.2</span>
<h3>查询平均价格大于 10 的产品分类</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT
category,
AVG(price) AS average_price
FROM products
GROUP BY category
HAVING AVG(price) > 10;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/09-02.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/09-02.png</span>
</div>
<img src="docs/screenshots/09-02.png" alt="9.2 查询平均价格大于 10 的产品分类 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/09-02.png</code></figcaption>
</figure>
</article><section class="section-title" id="section-10">
<p>Section 10</p>
<h2>第 10 部分：单表 INSERT / UPDATE / DELETE</h2>
</section><article class="sql-card" id="sql-10-01" data-title="10.1 新增一个客户" data-section="10" data-tag="单表 INSERT / UPDATE / DELETE">
<div class="card-head">
<div>
<span class="badge">10.1</span>
<h3>新增一个客户</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">INSERT INTO customers (name, city, email, level, created_at)
VALUES ('Grace Yang', 'Toronto', 'grace@example.com', 'normal', CURDATE());</code></pre>
<figure class="screenshot" data-path="docs/screenshots/10-01.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/10-01.png</span>
</div>
<img src="docs/screenshots/10-01.png" alt="10.1 新增一个客户 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/10-01.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-10-02" data-title="10.2 查看刚新增的客户" data-section="10" data-tag="单表 INSERT / UPDATE / DELETE">
<div class="card-head">
<div>
<span class="badge">10.2</span>
<h3>查看刚新增的客户</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT *
FROM customers
WHERE email = 'grace@example.com';</code></pre>
<figure class="screenshot" data-path="docs/screenshots/10-02.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/10-02.png</span>
</div>
<img src="docs/screenshots/10-02.png" alt="10.2 查看刚新增的客户 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/10-02.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-10-03" data-title="10.3 修改 Grace 的会员等级" data-section="10" data-tag="单表 INSERT / UPDATE / DELETE">
<div class="card-head">
<div>
<span class="badge">10.3</span>
<h3>修改 Grace 的会员等级</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">UPDATE customers
SET level = 'vip'
WHERE email = 'grace@example.com';</code></pre>
<figure class="screenshot" data-path="docs/screenshots/10-03.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/10-03.png</span>
</div>
<img src="docs/screenshots/10-03.png" alt="10.3 修改 Grace 的会员等级 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/10-03.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-10-04" data-title="10.4 删除 Grace" data-section="10" data-tag="单表 INSERT / UPDATE / DELETE">
<div class="card-head">
<div>
<span class="badge">10.4</span>
<h3>删除 Grace</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">DELETE FROM customers
WHERE email = 'grace@example.com';</code></pre>
<figure class="screenshot" data-path="docs/screenshots/10-04.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/10-04.png</span>
</div>
<img src="docs/screenshots/10-04.png" alt="10.4 删除 Grace 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/10-04.png</code></figcaption>
</figure>
</article><section class="section-title" id="section-11">
<p>Section 11</p>
<h2>第 11 部分：连接查询 JOIN</h2>
</section><article class="sql-card" id="sql-11-01" data-title="11.1 查询订单及对应客户信息" data-section="11" data-tag="连接查询 JOIN">
<div class="card-head">
<div>
<span class="badge">11.1</span>
<h3>查询订单及对应客户信息</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT
o.id AS order_id,
o.order_no,
o.status,
o.order_date,
c.name AS customer_name,
c.city
FROM orders o
INNER JOIN customers c ON o.customer_id = c.id
ORDER BY o.order_date DESC;</code></pre>
<figure class="screenshot" data-path="docs/screenshots/11-01.png">
<div class="shot-placeholder">
<strong>运行结果截图待上传</strong>
<span>docs/screenshots/11-01.png</span>
</div>
<img src="docs/screenshots/11-01.png" alt="11.1 查询订单及对应客户信息 运行结果截图" loading="lazy" onerror="this.style.display='none'; this.previousElementSibling.style.display='flex';" onload="this.previousElementSibling.style.display='none';">
<figcaption>截图路径：<code>docs/screenshots/11-01.png</code></figcaption>
</figure>
</article><article class="sql-card" id="sql-11-02" data-title="11.2 查询订单明细，包括订单号、客户、产品、数量、单价" data-section="11" data-tag="连接查询 JOIN">
<div class="card-head">
<div>
<span class="badge">11.2</span>
<h3>查询订单明细，包括订单号、客户、产品、数量、单价</h3>
</div>
<button class="copy-btn" type="button">复制 SQL</button>
</div>
<pre><code class="language-sql">SELECT
o.order_no,
c.name AS customer_name,