diff --git a/src/App.css b/src/App.css
index af95038..376bd76 100644
--- a/src/App.css
+++ b/src/App.css
@@ -779,3 +779,101 @@ footer {
     transition-duration: 0.01ms !important;
   }
 }
+
+/* ---------------------------------------------------------------------------
+   Table cells for the 2016-only identity columns.
+   Ported from the 2016 frontend; hidden automatically on the 2017 datasets
+   because every row there is NULL.
+   --------------------------------------------------------------------------- */
+
+.sbd-cell {
+  font-family: ui-monospace, monospace;
+  font-size: 0.85rem;
+  color: var(--text-muted);
+  white-space: nowrap;
+}
+
+.cumthi-cell {
+  font-size: 0.82rem;
+  color: var(--text-muted);
+  max-width: 220px;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
+/* ---------------------------------------------------------------------------
+   Hub route (/thptqg/) — replaces the old standalone static index.html
+   --------------------------------------------------------------------------- */
+
+.hub {
+  max-width: 42rem;
+  margin: 3rem auto;
+  padding: 0 1rem;
+  line-height: 1.6;
+}
+
+.hub h1 {
+  font-size: 1.5rem;
+  margin-bottom: 0.5rem;
+}
+
+.hub-list {
+  list-style: none;
+  padding: 0;
+  margin: 1.5rem 0;
+  display: grid;
+  gap: 0.75rem;
+}
+
+.hub-link {
+  display: flex;
+  flex-wrap: wrap;
+  align-items: baseline;
+  gap: 0.25rem 0.75rem;
+  padding: 0.9rem 1.1rem;
+  border: 1px solid var(--border);
+  border-radius: 10px;
+  background: var(--surface, transparent);
+  text-decoration: none;
+  color: inherit;
+}
+
+.hub-link:hover,
+.hub-link:focus-visible {
+  border-color: var(--border-strong);
+}
+
+.hub-label {
+  font-weight: 600;
+}
+
+.hub-blurb {
+  color: var(--text-muted);
+  font-size: 0.9rem;
+}
+
+.hub-archive h2 {
+  font-size: 0.95rem;
+  font-weight: 600;
+  color: var(--text-muted);
+  margin-bottom: 0;
+}
+
+.hub-list-compact {
+  margin-top: 0.75rem;
+}
+
+.hub-back {
+  margin: 0.35rem 0 0;
+  font-size: 0.85rem;
+}
+
+.hub-back a {
+  color: var(--text-muted);
+  text-decoration: none;
+}
+
+.hub-back a:hover {
+  text-decoration: underline;
+}
diff --git a/src/App.jsx b/src/App.jsx
index 94646c7..7e59bd2 100644
--- a/src/App.jsx
+++ b/src/App.jsx
@@ -4,17 +4,19 @@ import { SearchForm } from "./components/search-form";
 import { ScoreTable } from "./components/score-table";
 import { StudentDetail } from "./components/student-detail";
 import { CustomQuery } from "./components/custom-query";
+import { Hub } from "./components/hub";
+import { dbOf } from "./datasets";
+import { resolveRoute } from "./router";
+import { isExamId, normaliseExamId } from "./lib/query-mode";
 import "./App.css";
 
-const DB_URL = import.meta.env.BASE_URL + "thptqg2017.db.gz";
 const MAX_RESULTS = 100;
-const DB_SIZE_MB = 47;
 
 // Strip Vietnamese diacritics: "Nguyễn Bửu Lộc" → "nguyen buu loc"
 function toAscii(str) {
   return str
     .normalize("NFD")
-    .replace(/[\u0300-\u036f]/g, "")
+    .replace(/[̀-ͯ]/g, "")
     .replace(/đ/gi, "d")
     .toLowerCase();
 }
@@ -38,8 +40,11 @@ function readUrlQuery() {
   return new URL(window.location.href).searchParams.get("q") || "";
 }
 
-function App() {
-  const { db, loading, error, progress } = useSqlite(DB_URL);
+/** The score-lookup view for one dataset. */
+function DatasetApp({ dataset }) {
+  const { db, loading, error, progress } = useSqlite(
+    dbOf(dataset, import.meta.env.BASE_URL),
+  );
   const [results, setResults] = useState(null);
   const [searchError, setSearchError] = useState(null);
   const [activeTab, setActiveTab] = useState("search");
@@ -55,14 +60,14 @@ function App() {
       writeUrlQuery(q);
 
       try {
-        const isExamId = /^\d+$/.test(q);
         let stmt;
 
-        if (isExamId) {
+        if (isExamId(q)) {
+          // Letter-prefixed 2016 IDs are stored upper-case; digits are unaffected.
           stmt = db.prepare(
             "SELECT * FROM student WHERE so_bao_danh = $q LIMIT $limit",
           );
-          stmt.bind({ $q: q, $limit: MAX_RESULTS });
+          stmt.bind({ $q: normaliseExamId(q), $limit: MAX_RESULTS });
         } else if (isAsciiOnly(q)) {
           stmt = db.prepare(
             "SELECT * FROM student WHERE ho_ten_ascii LIKE $q LIMIT $limit",
@@ -141,9 +146,10 @@ function App() {
   return (
     <div className="app">
       <header>
-        <h1>Tra cứu điểm thi THPT Quốc gia 2017</h1>
-        <p className="subtitle">
-          Dữ liệu thí sinh toàn quốc · Hỗ trợ truy vấn SQL tùy chỉnh
+        <h1>{dataset.title}</h1>
+        <p className="subtitle">{dataset.subtitle}</p>
+        <p className="hub-back">
+          <a href={import.meta.env.BASE_URL}>← Tất cả các kỳ thi</a>
         </p>
       </header>
 
@@ -151,7 +157,7 @@ function App() {
         {loading && (
           <div className="loading">
             <p>
-              Đang tải cơ sở dữ liệu ~{DB_SIZE_MB} MB
+              Đang tải cơ sở dữ liệu ~{dataset.dbSizeMb} MB
               {progress > 0 ? ` · ${progress}%` : ""}
             </p>
             <div className="progress-bar">
@@ -188,6 +194,7 @@ function App() {
               onSearch={handleSearch}
               onClear={handleClear}
               disabled={loading || !!error}
+              examples={dataset.examples}
             />
 
             {searchError && (
@@ -209,13 +216,17 @@ function App() {
         )}
 
         {activeTab === "sql" && (
-          <CustomQuery db={db} disabled={loading || !!error} />
+          <CustomQuery
+            db={db}
+            disabled={loading || !!error}
+            presets={dataset.presets}
+          />
         )}
       </main>
 
       <footer>
         <p>
-          Nguồn: baotintuc.vn
+          Nguồn: {dataset.source}
           {totalCount !== null && ` · ${totalCount.toLocaleString("vi-VN")} thí sinh`}
           {" · Dữ liệu chỉ mang tính tham khảo"}
         </p>
@@ -224,4 +235,12 @@ function App() {
   );
 }
 
+function App() {
+  // Resolved once at mount: every route is a full page load on GitHub Pages,
+  // so there is no in-app navigation to react to.
+  const [dataset] = useState(() => resolveRoute());
+
+  return dataset ? <DatasetApp dataset={dataset} /> : <Hub />;
+}
+
 export default App;
diff --git a/src/components/custom-query.jsx b/src/components/custom-query.jsx
index 780ead0..99fcba5 100644
--- a/src/components/custom-query.jsx
+++ b/src/components/custom-query.jsx
@@ -2,179 +2,11 @@ import { useState, useCallback, useEffect } from "react";
 
 const MAX_ROWS = 1000;
 
-const PRESET_GROUPS = [
-  {
-    category: "Xếp hạng môn",
-    queries: [
-      {
-        label: "Top 10 điểm Toán",
-        sql: `SELECT so_bao_danh, ho_ten, ngay_sinh, toan
-FROM student WHERE toan IS NOT NULL
-ORDER BY toan DESC LIMIT 10`,
-      },
-      {
-        label: "Top 10 KHTN",
-        sql: `SELECT so_bao_danh, ho_ten, vat_ly, hoa_hoc, sinh_hoc, khtn
-FROM student WHERE khtn IS NOT NULL
-ORDER BY khtn DESC LIMIT 10`,
-      },
-      {
-        label: "Top 10 KHXH",
-        sql: `SELECT so_bao_danh, ho_ten, lich_su, dia_ly, gdcd, khxh
-FROM student WHERE khxh IS NOT NULL
-ORDER BY khxh DESC LIMIT 10`,
-      },
-      {
-        label: "Thí sinh ≥ 9 điểm Toán",
-        sql: `SELECT so_bao_danh, ho_ten, ngay_sinh, toan
-FROM student WHERE toan >= 9
-ORDER BY toan DESC LIMIT 50`,
-      },
-    ],
-  },
-  {
-    category: "Long An (SBD 49xxx)",
-    queries: [
-      {
-        label: "Top 10 Toán - Long An",
-        sql: `SELECT so_bao_danh, ho_ten, ngay_sinh, toan
-FROM student
-WHERE so_bao_danh LIKE '49%' AND toan IS NOT NULL
-ORDER BY toan DESC LIMIT 10`,
-      },
-      {
-        label: "Top 10 khối A - Long An",
-        sql: `SELECT so_bao_danh, ho_ten, toan, vat_ly, hoa_hoc,
-  ROUND(toan + vat_ly + hoa_hoc, 2) AS tong_khoi_a
-FROM student
-WHERE so_bao_danh LIKE '49%'
-  AND toan IS NOT NULL AND vat_ly IS NOT NULL AND hoa_hoc IS NOT NULL
-ORDER BY tong_khoi_a DESC LIMIT 10`,
-      },
-      {
-        // Top 100 Long An students by their best of 49 official 2017
-        // admission blocks. Each (student, block) pair is materialised via
-        // UNION ALL; ROW_NUMBER picks each student's #1 block; the outer
-        // SELECT ranks across students. Result includes the winning block
-        // code so the user sees which combination produced the score.
-        label: "Top 10 điểm khối cao nhất - Long An",
-        sql: `WITH per_block AS (
-  SELECT so_bao_danh, ho_ten, ngay_sinh, 'A00' k, toan+vat_ly+hoa_hoc s FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A01', toan+vat_ly+tieng_anh   FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A02', toan+vat_ly+sinh_hoc    FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A03', toan+vat_ly+lich_su     FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A04', toan+vat_ly+dia_ly      FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A05', toan+hoa_hoc+lich_su    FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A06', toan+hoa_hoc+dia_ly     FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A07', toan+lich_su+dia_ly     FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A08', toan+lich_su+gdcd       FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A09', toan+dia_ly+gdcd        FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A10', toan+vat_ly+gdcd        FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A11', toan+hoa_hoc+gdcd       FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'B00', toan+hoa_hoc+sinh_hoc   FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'B01', toan+sinh_hoc+lich_su   FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'B02', toan+sinh_hoc+dia_ly    FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'B03', toan+sinh_hoc+ngu_van   FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'B04', toan+sinh_hoc+gdcd      FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'B08', toan+sinh_hoc+tieng_anh FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C00', ngu_van+lich_su+dia_ly  FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C01', ngu_van+toan+vat_ly     FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C02', ngu_van+toan+hoa_hoc    FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C03', ngu_van+toan+lich_su    FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C04', ngu_van+toan+dia_ly     FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C05', ngu_van+vat_ly+hoa_hoc  FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C06', ngu_van+vat_ly+sinh_hoc FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C07', ngu_van+vat_ly+lich_su  FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C08', ngu_van+hoa_hoc+sinh_hoc FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C09', ngu_van+vat_ly+dia_ly   FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C10', ngu_van+hoa_hoc+lich_su FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C12', ngu_van+sinh_hoc+lich_su FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C13', ngu_van+sinh_hoc+dia_ly FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C14', ngu_van+toan+gdcd       FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C16', ngu_van+vat_ly+gdcd     FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C17', ngu_van+hoa_hoc+gdcd    FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C19', ngu_van+lich_su+gdcd    FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C20', ngu_van+dia_ly+gdcd     FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D01', toan+ngu_van+tieng_anh  FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D02', toan+ngu_van+tieng_nga  FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D03', toan+ngu_van+tieng_phap FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D04', toan+ngu_van+tieng_trung FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D07', toan+hoa_hoc+tieng_anh  FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D08', toan+sinh_hoc+tieng_anh FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D09', toan+lich_su+tieng_anh  FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D10', toan+dia_ly+tieng_anh   FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D11', ngu_van+vat_ly+tieng_anh FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D12', ngu_van+hoa_hoc+tieng_anh FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D13', ngu_van+sinh_hoc+tieng_anh FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D14', ngu_van+lich_su+tieng_anh FROM student WHERE so_bao_danh LIKE '49%'
-  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D15', ngu_van+dia_ly+tieng_anh FROM student WHERE so_bao_danh LIKE '49%'
-),
-ranked AS (
-  SELECT *, ROW_NUMBER() OVER (PARTITION BY so_bao_danh ORDER BY s DESC, k) rn
-  FROM per_block WHERE s IS NOT NULL
-)
-SELECT so_bao_danh, ho_ten, ngay_sinh, k AS khoi, ROUND(s, 2) AS diem
-FROM ranked WHERE rn = 1
-ORDER BY diem DESC LIMIT 10`,
-      },
-    ],
-  },
-  {
-    category: "Thống kê",
-    queries: [
-      {
-        label: "Phân bố điểm Toán",
-        sql: `SELECT
-  CASE
-    WHEN toan < 1 THEN '0-1'
-    WHEN toan < 2 THEN '1-2'
-    WHEN toan < 3 THEN '2-3'
-    WHEN toan < 4 THEN '3-4'
-    WHEN toan < 5 THEN '4-5'
-    WHEN toan < 6 THEN '5-6'
-    WHEN toan < 7 THEN '6-7'
-    WHEN toan < 8 THEN '7-8'
-    WHEN toan < 9 THEN '8-9'
-    ELSE '9-10'
-  END AS khoang_diem,
-  COUNT(*) AS so_luong
-FROM student WHERE toan IS NOT NULL
-GROUP BY khoang_diem
-ORDER BY khoang_diem`,
-      },
-      {
-        label: "Số TS theo ngoại ngữ",
-        sql: `SELECT
-  SUM(CASE WHEN tieng_anh   IS NOT NULL THEN 1 ELSE 0 END) AS tieng_anh,
-  SUM(CASE WHEN tieng_phap  IS NOT NULL THEN 1 ELSE 0 END) AS tieng_phap,
-  SUM(CASE WHEN tieng_nga   IS NOT NULL THEN 1 ELSE 0 END) AS tieng_nga,
-  SUM(CASE WHEN tieng_trung IS NOT NULL THEN 1 ELSE 0 END) AS tieng_trung
-FROM student`,
-      },
-      {
-        label: "KHTN vs KHXH",
-        sql: `SELECT
-  SUM(CASE WHEN khtn IS NOT NULL THEN 1 ELSE 0 END) AS chon_khtn,
-  SUM(CASE WHEN khxh IS NOT NULL THEN 1 ELSE 0 END) AS chon_khxh,
-  SUM(CASE WHEN khtn IS NOT NULL AND khxh IS NOT NULL THEN 1 ELSE 0 END) AS chon_ca_hai
-FROM student`,
-      },
-    ],
-  },
-  {
-    category: "Hệ thống",
-    queries: [
-      {
-        label: "Schema bảng student",
-        sql: `PRAGMA table_info(student)`,
-      },
-    ],
-  },
-];
+export function CustomQuery({ db, disabled, presets = [] }) {
+  // Every preset set ends with a "Hệ thống" group whose first query dumps the
+  // table schema; that is what gets auto-run when the tab first opens.
+  const schemaPreset = presets[presets.length - 1]?.queries[0];
 
-const SCHEMA_PRESET = PRESET_GROUPS[PRESET_GROUPS.length - 1].queries[0];
-
-export function CustomQuery({ db, disabled }) {
   const [sql, setSql] = useState("");
   const [columns, setColumns] = useState([]);
   const [rows, setRows] = useState([]);
@@ -249,9 +81,9 @@ export function CustomQuery({ db, disabled }) {
   // Auto-run the schema preset the first time the tab is opened so the user
   // sees the student columns instead of a blank textarea.
   useEffect(() => {
-    if (db && columns.length === 0 && !sql) {
-      executeQuery(SCHEMA_PRESET.sql);
-      setSql(SCHEMA_PRESET.sql);
+    if (db && schemaPreset && columns.length === 0 && !sql) {
+      executeQuery(schemaPreset.sql);
+      setSql(schemaPreset.sql);
     }
     // eslint-disable-next-line react-hooks/exhaustive-deps
   }, [db]);
@@ -259,7 +91,7 @@ export function CustomQuery({ db, disabled }) {
   return (
     <div className="custom-query">
       <div className="preset-groups">
-        {PRESET_GROUPS.map((group) => (
+        {presets.map((group) => (
           <div key={group.category} className="preset-group">
             <span className="preset-label">{group.category}</span>
             <div className="preset-list">
diff --git a/src/components/hub.jsx b/src/components/hub.jsx
new file mode 100644
index 0000000..9343759
--- /dev/null
+++ b/src/components/hub.jsx
@@ -0,0 +1,57 @@
+import { DATASETS, pathOf } from "../datasets";
+
+/**
+ * The /thptqg/ landing route.
+ *
+ * Replaces the hand-written static index.html the repo used to serve here, so
+ * the hub shares the app's styling and dataset list instead of repeating them.
+ * No database is fetched on this route.
+ */
+export function Hub() {
+  const current = DATASETS.filter((d) => !d.id.includes("old"));
+  const archived = DATASETS.filter((d) => d.id.includes("old"));
+  const base = import.meta.env.BASE_URL;
+
+  return (
+    <div className="hub">
+      <header>
+        <h1>Tra cứu điểm thi THPT Quốc gia</h1>
+        <p className="subtitle">
+          Tra cứu điểm thi tốt nghiệp THPT Quốc gia theo số báo danh — truy vấn
+          SQL chạy hoàn toàn trên trình duyệt (sql.js).
+        </p>
+      </header>
+
+      <main>
+        <ul className="hub-list" role="list">
+          {current.map((d) => (
+            <li key={d.id}>
+              <a className="hub-link" href={pathOf(d, base)}>
+                <span className="hub-label">{d.label}</span>
+                <span className="hub-blurb">{d.blurb}</span>
+              </a>
+            </li>
+          ))}
+        </ul>
+
+        <section className="hub-archive" aria-labelledby="archive-heading">
+          <h2 id="archive-heading">Phiên bản cũ của trang 2017</h2>
+          <ul className="hub-list hub-list-compact" role="list">
+            {archived.map((d) => (
+              <li key={d.id}>
+                <a className="hub-link" href={pathOf(d, base)}>
+                  <span className="hub-label">{d.label}</span>
+                  <span className="hub-blurb">{d.blurb}</span>
+                </a>
+              </li>
+            ))}
+          </ul>
+        </section>
+      </main>
+
+      <footer>
+        <p>Dữ liệu chỉ mang tính tham khảo.</p>
+      </footer>
+    </div>
+  );
+}
diff --git a/src/components/score-table.jsx b/src/components/score-table.jsx
index a43c576..07f70ce 100644
--- a/src/components/score-table.jsx
+++ b/src/components/score-table.jsx
@@ -1,21 +1,5 @@
 import { scoreTier } from "../lib/admission-blocks";
-
-const SUBJECT_COLUMNS = [
-  { key: "toan", label: "Toán" },
-  { key: "ngu_van", label: "Ngữ văn" },
-  { key: "vat_ly", label: "Vật lí" },
-  { key: "hoa_hoc", label: "Hóa học" },
-  { key: "sinh_hoc", label: "Sinh học" },
-  { key: "khtn", label: "KHTN" },
-  { key: "lich_su", label: "Lịch sử" },
-  { key: "dia_ly", label: "Địa lí" },
-  { key: "gdcd", label: "GDCD" },
-  { key: "khxh", label: "KHXH" },
-  { key: "tieng_anh", label: "Tiếng Anh" },
-  { key: "tieng_phap", label: "Tiếng Pháp" },
-  { key: "tieng_nga", label: "Tiếng Nga" },
-  { key: "tieng_trung", label: "Tiếng Trung" },
-];
+import { SUBJECTS, IDENTITY_COLUMNS, hasAnyValue } from "../lib/subjects";
 
 function formatScore(val) {
   if (val === null || val === undefined) return "—";
@@ -28,10 +12,14 @@ export function ScoreTable({ results }) {
     return <p className="no-results">Không tìm thấy kết quả.</p>;
   }
 
-  // Hide columns where every row in the result set is null (e.g. unused foreign langs)
-  const visibleColumns = SUBJECT_COLUMNS.filter((col) =>
-    results.some((row) => row[col.key] !== null && row[col.key] !== undefined),
+  // Drop columns where every row in the result set is NULL. This is what makes
+  // one table serve both exam years: 2016 rows surface Cụm thi / GT / Đức /
+  // Nhật and hide KHTN / KHXH / GDCD / Nga, and 2017 rows do the reverse — with
+  // no dataset conditional anywhere in this component.
+  const visibleIdentity = IDENTITY_COLUMNS.filter((col) =>
+    hasAnyValue(results, col.key),
   );
+  const visibleSubjects = SUBJECTS.filter((col) => hasAnyValue(results, col.key));
 
   return (
     <div className="table-wrapper">
@@ -42,7 +30,10 @@ export function ScoreTable({ results }) {
             <th>SBD</th>
             <th>Họ tên</th>
             <th>Ngày sinh</th>
-            {visibleColumns.map((col) => (
+            {visibleIdentity.map((col) => (
+              <th key={col.key}>{col.label}</th>
+            ))}
+            {visibleSubjects.map((col) => (
               <th key={col.key}>{col.label}</th>
             ))}
           </tr>
@@ -50,10 +41,19 @@ export function ScoreTable({ results }) {
         <tbody>
           {results.map((row) => (
             <tr key={row.so_bao_danh}>
-              <td>{row.so_bao_danh}</td>
+              <td className="sbd-cell">{row.so_bao_danh}</td>
               <td className="name-cell">{row.ho_ten}</td>
               <td>{row.ngay_sinh || "—"}</td>
-              {visibleColumns.map((col) => {
+              {visibleIdentity.map((col) => (
+                <td
+                  key={col.key}
+                  className={col.key === "ten_cum_thi" ? "cumthi-cell" : undefined}
+                  title={col.key === "ten_cum_thi" ? row[col.key] || "" : undefined}
+                >
+                  {row[col.key] || "—"}
+                </td>
+              ))}
+              {visibleSubjects.map((col) => {
                 const tier = scoreTier(row[col.key]);
                 const cls = tier ? `score-cell tier-${tier.key}` : "score-cell";
                 return (
diff --git a/src/components/search-form.jsx b/src/components/search-form.jsx
index c8e69a9..180590c 100644
--- a/src/components/search-form.jsx
+++ b/src/components/search-form.jsx
@@ -1,25 +1,15 @@
 import { useEffect, useRef, useState } from "react";
+import { detectMode } from "../lib/query-mode";
 
 const DEBOUNCE_MS = 300;
-const MIN_SBD_DIGITS = 3;
-const MIN_NAME_CHARS = 2;
-const EXAMPLES = ["49008235", "Nguyễn Minh Tiến"];
 
-// Detect input mode for dynamic hint shown under the field
-function detectMode(raw) {
-  const q = raw.trim();
-  if (!q) return { mode: "empty", hint: "Gõ SBD (chữ số) hoặc họ tên để tìm" };
-  if (/^\d+$/.test(q)) {
-    return q.length >= MIN_SBD_DIGITS
-      ? { mode: "sbd", hint: `Tìm theo số báo danh · khớp chính xác` }
-      : { mode: "sbd-short", hint: `Cần ít nhất ${MIN_SBD_DIGITS} chữ số` };
-  }
-  return q.length >= MIN_NAME_CHARS
-    ? { mode: "name", hint: "Tìm theo họ tên · không phân biệt dấu và hoa/thường" }
-    : { mode: "name-short", hint: `Cần ít nhất ${MIN_NAME_CHARS} ký tự` };
-}
-
-export function SearchForm({ value = "", onSearch, onClear, disabled }) {
+export function SearchForm({
+  value = "",
+  onSearch,
+  onClear,
+  disabled,
+  examples = [],
+}) {
   const [query, setQuery] = useState(value);
   const inputRef = useRef(null);
   const timerRef = useRef(null);
@@ -104,7 +94,7 @@ export function SearchForm({ value = "", onSearch, onClear, disabled }) {
         {mode === "empty" && (
           <>
             {" · VD: "}
-            {EXAMPLES.map((ex, i) => (
+            {examples.map((ex, i) => (
               <span key={ex}>
                 <button
                   type="button"
@@ -116,7 +106,7 @@ export function SearchForm({ value = "", onSearch, onClear, disabled }) {
                 >
                   {ex}
                 </button>
-                {i < EXAMPLES.length - 1 ? " hoặc " : ""}
+                {i < examples.length - 1 ? " hoặc " : ""}
               </span>
             ))}
           </>
diff --git a/src/components/student-detail.jsx b/src/components/student-detail.jsx
index 7477513..1cdc399 100644
--- a/src/components/student-detail.jsx
+++ b/src/components/student-detail.jsx
@@ -1,29 +1,6 @@
 import { useState } from "react";
 import { computeBlocks, scoreTier } from "../lib/admission-blocks";
-
-const SUBJECT_LABELS = {
-  toan: "Toán",
-  ngu_van: "Ngữ văn",
-  vat_ly: "Vật lí",
-  hoa_hoc: "Hóa học",
-  sinh_hoc: "Sinh học",
-  khtn: "KHTN",
-  lich_su: "Lịch sử",
-  dia_ly: "Địa lí",
-  gdcd: "GDCD",
-  khxh: "KHXH",
-  tieng_anh: "Tiếng Anh",
-  tieng_phap: "Tiếng Pháp",
-  tieng_nga: "Tiếng Nga",
-  tieng_trung: "Tiếng Trung",
-};
-
-const SUBJECT_ORDER = [
-  "toan", "ngu_van",
-  "vat_ly", "hoa_hoc", "sinh_hoc", "khtn",
-  "lich_su", "dia_ly", "gdcd", "khxh",
-  "tieng_anh", "tieng_phap", "tieng_nga", "tieng_trung",
-];
+import { SUBJECTS } from "../lib/subjects";
 
 function fmt(n) {
   return n === null || n === undefined ? "—" : Number(n).toFixed(2);
@@ -43,9 +20,9 @@ const TIER_LEGEND = [
 export function StudentDetail({ student }) {
   const [copied, setCopied] = useState(null);  // null | 'sbd' | 'share' | 'url'
   const blocks = computeBlocks(student);
-  const subjects = SUBJECT_ORDER
-    .filter((k) => student[k] !== null && student[k] !== undefined)
-    .map((k) => ({ key: k, label: SUBJECT_LABELS[k], score: student[k] }));
+  const subjects = SUBJECTS
+    .filter((s) => student[s.key] !== null && student[s.key] !== undefined)
+    .map((s) => ({ key: s.key, label: s.label, score: student[s.key] }));
 
   function flash(kind) {
     setCopied(kind);
@@ -108,6 +85,19 @@ export function StudentDetail({ student }) {
                 <dd className="mono">{student.ngay_sinh}</dd>
               </div>
             )}
+            {/* Only the 2016 dataset carries these; NULL elsewhere. */}
+            {student.ten_cum_thi && (
+              <div>
+                <dt>Cụm thi</dt>
+                <dd>{student.ten_cum_thi}</dd>
+              </div>
+            )}
+            {student.gioi_tinh && (
+              <div>
+                <dt>Giới tính</dt>
+                <dd>{student.gioi_tinh}</dd>
+              </div>
+            )}
           </dl>
         </div>
         <div className="detail-actions">
diff --git a/src/datasets.js b/src/datasets.js
index 18ed58d..96b5c73 100644
--- a/src/datasets.js
+++ b/src/datasets.js
@@ -5,31 +5,68 @@
  *
  *   data/<id>/  →  parser/configs/<id>.toml  →  db/<id>.db.gz  →  /thptqg/<id>/
  *
+ * Site path and database URL are derived from `id` rather than stored, so a
+ * dataset cannot be misconfigured into pointing at the wrong database.
+ *
  * Imported by the Vite app *and* by parser/scripts/build-db.js under plain
  * Node, so this module must stay free of `import.meta.env` and any Vite-only
  * syntax. Callers pass the base URL in explicitly for that reason.
  */
 
+// Extension is required: this module is also imported by plain Node
+// (parser/scripts/build-db.js), which does not resolve extensionless paths.
+import { PRESETS_2016, PRESETS_2017 } from "./lib/sql-presets.js";
+
+const SUBTITLE = "Dữ liệu thí sinh toàn quốc · Hỗ trợ truy vấn SQL tùy chỉnh";
+
 export const DATASETS = [
   {
     id: "2016",
     year: 2016,
     label: "Kỳ thi 2016",
+    blurb: "877.461 thí sinh",
+    title: "Tra cứu điểm thi THPT Quốc gia 2016",
+    subtitle: SUBTITLE,
+    source: "Bộ GD&ĐT",
+    dbSizeMb: 44,
+    examples: ["17006021", "Nguyễn Thị Hoa"],
+    presets: PRESETS_2016,
   },
   {
     id: "2017",
     year: 2017,
     label: "Kỳ thi 2017",
+    blurb: "861.068 thí sinh",
+    title: "Tra cứu điểm thi THPT Quốc gia 2017",
+    subtitle: SUBTITLE,
+    source: "baotintuc.vn",
+    dbSizeMb: 48,
+    examples: ["49008235", "Nguyễn Minh Tiến"],
+    presets: PRESETS_2017,
   },
   {
     id: "2017-old",
     year: 2017,
     label: "2017 — bản cũ",
+    blurb: "847.348 thí sinh · bản trước khi cập nhật",
+    title: "Tra cứu điểm thi THPT Quốc gia 2017 (bản cũ)",
+    subtitle: SUBTITLE,
+    source: "bản lưu trước đợt cập nhật baotintuc.vn",
+    dbSizeMb: 47,
+    examples: ["49008235", "Nguyễn Minh Tiến"],
+    presets: PRESETS_2017,
   },
   {
     id: "2017-old2",
     year: 2017,
     label: "2017 — bản cũ 2",
+    blurb: "679.764 thí sinh · bản xuất lại",
+    title: "Tra cứu điểm thi THPT Quốc gia 2017 (bản cũ 2)",
+    subtitle: SUBTITLE,
+    source: "bản xuất lại đã hiệu chỉnh",
+    dbSizeMb: 38,
+    examples: ["49008235", "Nguyễn Minh Tiến"],
+    presets: PRESETS_2017,
   },
 ];
 
diff --git a/src/lib/admission-blocks.js b/src/lib/admission-blocks.js
index 0119bae..15cb2f6 100644
--- a/src/lib/admission-blocks.js
+++ b/src/lib/admission-blocks.js
@@ -1,10 +1,13 @@
-// Vietnamese university admission-block ("khối thi") definitions for 2017.
+// Vietnamese university admission-block ("khối thi") definitions.
 // Each block is the sum of 3 subjects; we only compute a block when ALL three
 // subject scores exist for the student.
-
-// Full 2017 admission-block list (Circular 03/2017/TT-BGDĐT) restricted to
-// the 12 subjects available in our DB. Blocks needing Tiếng Đức / Nhật are
-// excluded — neither language appears in any source file.
+//
+// One list serves both exam years. computeBlocks() skips any block with a
+// missing subject score, so blocks needing GDCD self-exclude on 2016 rows and
+// blocks needing Tiếng Đức / Nhật self-exclude wherever those weren't sat —
+// no per-year branching required.
+//
+// Based on Circular 03/2017/TT-BGDĐT.
 export const ADMISSION_BLOCKS = [
   { code: "A00", subjects: ["toan", "vat_ly", "hoa_hoc"],     label: "Toán + Lý + Hóa" },
   { code: "A01", subjects: ["toan", "vat_ly", "tieng_anh"],   label: "Toán + Lý + Anh" },
@@ -55,6 +58,14 @@ export const ADMISSION_BLOCKS = [
   { code: "D13", subjects: ["ngu_van", "sinh_hoc", "tieng_anh"], label: "Văn + Sinh + Anh" },
   { code: "D14", subjects: ["ngu_van", "lich_su", "tieng_anh"], label: "Văn + Sử + Anh" },
   { code: "D15", subjects: ["ngu_van", "dia_ly", "tieng_anh"], label: "Văn + Địa + Anh" },
+
+  // German and Japanese blocks. Previously omitted because neither language
+  // appeared in the 2017 database — but that was a parser gap, not reality:
+  // unifying the subject patterns recovered German and Japanese scores in every
+  // dataset. Students who sat neither are unaffected, since computeBlocks()
+  // skips blocks with a missing subject.
+  { code: "D05", subjects: ["toan", "ngu_van", "tieng_duc"],  label: "Toán + Văn + Đức" },
+  { code: "D06", subjects: ["toan", "ngu_van", "tieng_nhat"], label: "Toán + Văn + Nhật" },
 ];
 
 // Returns { code, label, total, parts:[{key,score}] } for every block where
diff --git a/src/lib/query-mode.js b/src/lib/query-mode.js
new file mode 100644
index 0000000..0b7b869
--- /dev/null
+++ b/src/lib/query-mode.js
@@ -0,0 +1,59 @@
+/**
+ * Classify a search box query as an exam ID (số báo danh) or a name.
+ *
+ * Shared by App.jsx and search-form.jsx. They previously carried separate
+ * copies of this rule and had already drifted: the 2016 app matched
+ * `/^[A-Z]{2,4}\d+$/i || /^\d+$/` while the 2017 app matched only `/^\d+$/`.
+ *
+ * SBD formats across both exam years:
+ *
+ *   49008235     2017 — 8 digits, first two identify the province
+ *   017006021    2016 — 9 digits including a leading zero
+ *   BAL000001    2016 — 2-4 letter exam-cluster code then digits
+ *
+ * That last form is not an edge case: 616,593 of 877,461 candidates in the
+ * 2016 dataset (70.3%) have a letter-prefixed SBD. Matching digits only would
+ * break exam-ID lookup for most of that year.
+ */
+
+const SBD_PATTERN = /^[A-Za-z]{0,4}\d+$/;
+
+export const MIN_SBD_DIGITS = 3;
+export const MIN_NAME_CHARS = 2;
+
+/** True when the query looks like an exam ID rather than a name. */
+export function isExamId(query) {
+  return SBD_PATTERN.test(query.trim());
+}
+
+/**
+ * Normalise an exam ID for lookup. Letter prefixes are stored upper-case, so a
+ * user typing "bal000001" still matches. No-op for all-digit IDs.
+ */
+export function normaliseExamId(query) {
+  return query.trim().toUpperCase();
+}
+
+function digitCount(str) {
+  return (str.match(/\d/g) ?? []).length;
+}
+
+/**
+ * Decide what the user is searching for, and what hint to show beneath the
+ * field. Returns `{ mode, hint }` where mode is one of:
+ * empty | sbd | sbd-short | name | name-short.
+ */
+export function detectMode(raw) {
+  const q = raw.trim();
+  if (!q) return { mode: "empty", hint: "Gõ SBD (số báo danh) hoặc họ tên để tìm" };
+
+  if (isExamId(q)) {
+    return digitCount(q) >= MIN_SBD_DIGITS
+      ? { mode: "sbd", hint: "Tìm theo số báo danh · khớp chính xác" }
+      : { mode: "sbd-short", hint: `Cần ít nhất ${MIN_SBD_DIGITS} chữ số` };
+  }
+
+  return q.length >= MIN_NAME_CHARS
+    ? { mode: "name", hint: "Tìm theo họ tên · không phân biệt dấu và hoa/thường" }
+    : { mode: "name-short", hint: `Cần ít nhất ${MIN_NAME_CHARS} ký tự` };
+}
diff --git a/src/lib/sql-presets.js b/src/lib/sql-presets.js
new file mode 100644
index 0000000..5b5661f
--- /dev/null
+++ b/src/lib/sql-presets.js
@@ -0,0 +1,280 @@
+/**
+ * SQL presets shown in the "Truy vấn SQL" tab, per dataset.
+ *
+ * These are genuinely dataset-specific and cannot be shared:
+ *   - 2016 has ten_cum_thi / gioi_tinh to group by, and no KHTN/KHXH/GDCD
+ *   - 2017 has the composite KHTN/KHXH scores, and its SBDs are province-
+ *     prefixed 8-digit numbers, which the Long An (49xxx) queries rely on
+ *
+ * Both end with a "Hệ thống" group whose first query is run automatically when
+ * the SQL tab is first opened, so the schema is visible before writing a query.
+ */
+
+export const PRESETS_2017 = [
+  {
+    category: "Xếp hạng môn",
+    queries: [
+      {
+        label: "Top 10 điểm Toán",
+        sql: `SELECT so_bao_danh, ho_ten, ngay_sinh, toan
+FROM student WHERE toan IS NOT NULL
+ORDER BY toan DESC LIMIT 10`,
+      },
+      {
+        label: "Top 10 KHTN",
+        sql: `SELECT so_bao_danh, ho_ten, vat_ly, hoa_hoc, sinh_hoc, khtn
+FROM student WHERE khtn IS NOT NULL
+ORDER BY khtn DESC LIMIT 10`,
+      },
+      {
+        label: "Top 10 KHXH",
+        sql: `SELECT so_bao_danh, ho_ten, lich_su, dia_ly, gdcd, khxh
+FROM student WHERE khxh IS NOT NULL
+ORDER BY khxh DESC LIMIT 10`,
+      },
+      {
+        label: "Thí sinh ≥ 9 điểm Toán",
+        sql: `SELECT so_bao_danh, ho_ten, ngay_sinh, toan
+FROM student WHERE toan >= 9
+ORDER BY toan DESC LIMIT 50`,
+      },
+    ],
+  },
+  {
+    category: "Long An (SBD 49xxx)",
+    queries: [
+      {
+        label: "Top 10 Toán - Long An",
+        sql: `SELECT so_bao_danh, ho_ten, ngay_sinh, toan
+FROM student
+WHERE so_bao_danh LIKE '49%' AND toan IS NOT NULL
+ORDER BY toan DESC LIMIT 10`,
+      },
+      {
+        label: "Top 10 khối A - Long An",
+        sql: `SELECT so_bao_danh, ho_ten, toan, vat_ly, hoa_hoc,
+  ROUND(toan + vat_ly + hoa_hoc, 2) AS tong_khoi_a
+FROM student
+WHERE so_bao_danh LIKE '49%'
+  AND toan IS NOT NULL AND vat_ly IS NOT NULL AND hoa_hoc IS NOT NULL
+ORDER BY tong_khoi_a DESC LIMIT 10`,
+      },
+      {
+        // Top 100 Long An students by their best of 49 official 2017
+        // admission blocks. Each (student, block) pair is materialised via
+        // UNION ALL; ROW_NUMBER picks each student's #1 block; the outer
+        // SELECT ranks across students. Result includes the winning block
+        // code so the user sees which combination produced the score.
+        label: "Top 10 điểm khối cao nhất - Long An",
+        sql: `WITH per_block AS (
+  SELECT so_bao_danh, ho_ten, ngay_sinh, 'A00' k, toan+vat_ly+hoa_hoc s FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A01', toan+vat_ly+tieng_anh   FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A02', toan+vat_ly+sinh_hoc    FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A03', toan+vat_ly+lich_su     FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A04', toan+vat_ly+dia_ly      FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A05', toan+hoa_hoc+lich_su    FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A06', toan+hoa_hoc+dia_ly     FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A07', toan+lich_su+dia_ly     FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A08', toan+lich_su+gdcd       FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A09', toan+dia_ly+gdcd        FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A10', toan+vat_ly+gdcd        FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'A11', toan+hoa_hoc+gdcd       FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'B00', toan+hoa_hoc+sinh_hoc   FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'B01', toan+sinh_hoc+lich_su   FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'B02', toan+sinh_hoc+dia_ly    FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'B03', toan+sinh_hoc+ngu_van   FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'B04', toan+sinh_hoc+gdcd      FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'B08', toan+sinh_hoc+tieng_anh FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C00', ngu_van+lich_su+dia_ly  FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C01', ngu_van+toan+vat_ly     FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C02', ngu_van+toan+hoa_hoc    FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C03', ngu_van+toan+lich_su    FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C04', ngu_van+toan+dia_ly     FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C05', ngu_van+vat_ly+hoa_hoc  FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C06', ngu_van+vat_ly+sinh_hoc FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C07', ngu_van+vat_ly+lich_su  FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C08', ngu_van+hoa_hoc+sinh_hoc FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C09', ngu_van+vat_ly+dia_ly   FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C10', ngu_van+hoa_hoc+lich_su FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C12', ngu_van+sinh_hoc+lich_su FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C13', ngu_van+sinh_hoc+dia_ly FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C14', ngu_van+toan+gdcd       FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C16', ngu_van+vat_ly+gdcd     FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C17', ngu_van+hoa_hoc+gdcd    FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C19', ngu_van+lich_su+gdcd    FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'C20', ngu_van+dia_ly+gdcd     FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D01', toan+ngu_van+tieng_anh  FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D02', toan+ngu_van+tieng_nga  FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D03', toan+ngu_van+tieng_phap FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D04', toan+ngu_van+tieng_trung FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D07', toan+hoa_hoc+tieng_anh  FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D08', toan+sinh_hoc+tieng_anh FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D09', toan+lich_su+tieng_anh  FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D10', toan+dia_ly+tieng_anh   FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D11', ngu_van+vat_ly+tieng_anh FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D12', ngu_van+hoa_hoc+tieng_anh FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D13', ngu_van+sinh_hoc+tieng_anh FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D14', ngu_van+lich_su+tieng_anh FROM student WHERE so_bao_danh LIKE '49%'
+  UNION ALL SELECT so_bao_danh, ho_ten, ngay_sinh, 'D15', ngu_van+dia_ly+tieng_anh FROM student WHERE so_bao_danh LIKE '49%'
+),
+ranked AS (
+  SELECT *, ROW_NUMBER() OVER (PARTITION BY so_bao_danh ORDER BY s DESC, k) rn
+  FROM per_block WHERE s IS NOT NULL
+)
+SELECT so_bao_danh, ho_ten, ngay_sinh, k AS khoi, ROUND(s, 2) AS diem
+FROM ranked WHERE rn = 1
+ORDER BY diem DESC LIMIT 10`,
+      },
+    ],
+  },
+  {
+    category: "Thống kê",
+    queries: [
+      {
+        label: "Phân bố điểm Toán",
+        sql: `SELECT
+  CASE
+    WHEN toan < 1 THEN '0-1'
+    WHEN toan < 2 THEN '1-2'
+    WHEN toan < 3 THEN '2-3'
+    WHEN toan < 4 THEN '3-4'
+    WHEN toan < 5 THEN '4-5'
+    WHEN toan < 6 THEN '5-6'
+    WHEN toan < 7 THEN '6-7'
+    WHEN toan < 8 THEN '7-8'
+    WHEN toan < 9 THEN '8-9'
+    ELSE '9-10'
+  END AS khoang_diem,
+  COUNT(*) AS so_luong
+FROM student WHERE toan IS NOT NULL
+GROUP BY khoang_diem
+ORDER BY khoang_diem`,
+      },
+      {
+        label: "Số TS theo ngoại ngữ",
+        sql: `SELECT
+  SUM(CASE WHEN tieng_anh   IS NOT NULL THEN 1 ELSE 0 END) AS tieng_anh,
+  SUM(CASE WHEN tieng_phap  IS NOT NULL THEN 1 ELSE 0 END) AS tieng_phap,
+  SUM(CASE WHEN tieng_nga   IS NOT NULL THEN 1 ELSE 0 END) AS tieng_nga,
+  SUM(CASE WHEN tieng_trung IS NOT NULL THEN 1 ELSE 0 END) AS tieng_trung
+FROM student`,
+      },
+      {
+        label: "KHTN vs KHXH",
+        sql: `SELECT
+  SUM(CASE WHEN khtn IS NOT NULL THEN 1 ELSE 0 END) AS chon_khtn,
+  SUM(CASE WHEN khxh IS NOT NULL THEN 1 ELSE 0 END) AS chon_khxh,
+  SUM(CASE WHEN khtn IS NOT NULL AND khxh IS NOT NULL THEN 1 ELSE 0 END) AS chon_ca_hai
+FROM student`,
+      },
+    ],
+  },
+  {
+    category: "Hệ thống",
+    queries: [
+      {
+        label: "Schema bảng student",
+        sql: `PRAGMA table_info(student)`,
+      },
+    ],
+  },
+];
+export const PRESETS_2016 = [
+  {
+    category: "Xếp hạng môn",
+    queries: [
+      {
+        label: "Top 10 điểm Toán",
+        sql: `SELECT so_bao_danh, ho_ten, ten_cum_thi, toan
+FROM student WHERE toan IS NOT NULL
+ORDER BY toan DESC LIMIT 10`,
+      },
+      {
+        label: "Thí sinh ≥ 9 điểm Toán",
+        sql: `SELECT so_bao_danh, ho_ten, ten_cum_thi, gioi_tinh, toan
+FROM student WHERE toan >= 9
+ORDER BY toan DESC LIMIT 50`,
+      },
+      {
+        label: "Top 10 khối A",
+        sql: `SELECT so_bao_danh, ho_ten, ten_cum_thi, toan, vat_ly, hoa_hoc,
+  ROUND(toan + vat_ly + hoa_hoc, 2) AS tong_khoi_a
+FROM student
+WHERE toan IS NOT NULL AND vat_ly IS NOT NULL AND hoa_hoc IS NOT NULL
+ORDER BY tong_khoi_a DESC LIMIT 10`,
+      },
+    ],
+  },
+  {
+    category: "Cụm thi & giới tính",
+    queries: [
+      {
+        label: "Điểm trung bình theo cụm thi",
+        sql: `SELECT ten_cum_thi,
+  COUNT(*) AS so_luong,
+  ROUND(AVG(toan), 2) AS tb_toan,
+  ROUND(AVG(ngu_van), 2) AS tb_van,
+  ROUND(AVG(tieng_anh), 2) AS tb_anh
+FROM student
+GROUP BY ten_cum_thi
+ORDER BY so_luong DESC
+LIMIT 20`,
+      },
+      {
+        label: "Thống kê theo giới tính",
+        sql: `SELECT gioi_tinh,
+  COUNT(*) AS so_luong,
+  ROUND(AVG(toan), 2) AS tb_toan,
+  ROUND(AVG(ngu_van), 2) AS tb_van
+FROM student
+WHERE gioi_tinh IS NOT NULL
+GROUP BY gioi_tinh`,
+      },
+    ],
+  },
+  {
+    category: "Thống kê",
+    queries: [
+      {
+        label: "Phân bố điểm Toán",
+        sql: `SELECT
+  CASE
+    WHEN toan < 1 THEN '0-1'
+    WHEN toan < 2 THEN '1-2'
+    WHEN toan < 3 THEN '2-3'
+    WHEN toan < 4 THEN '3-4'
+    WHEN toan < 5 THEN '4-5'
+    WHEN toan < 6 THEN '5-6'
+    WHEN toan < 7 THEN '6-7'
+    WHEN toan < 8 THEN '7-8'
+    WHEN toan < 9 THEN '8-9'
+    ELSE '9-10'
+  END AS khoang_diem,
+  COUNT(*) AS so_luong
+FROM student WHERE toan IS NOT NULL
+GROUP BY khoang_diem
+ORDER BY khoang_diem`,
+      },
+      {
+        label: "Số thí sinh theo ngoại ngữ",
+        sql: `SELECT
+  SUM(CASE WHEN tieng_anh   IS NOT NULL THEN 1 ELSE 0 END) AS tieng_anh,
+  SUM(CASE WHEN tieng_phap  IS NOT NULL THEN 1 ELSE 0 END) AS tieng_phap,
+  SUM(CASE WHEN tieng_nga   IS NOT NULL THEN 1 ELSE 0 END) AS tieng_nga,
+  SUM(CASE WHEN tieng_duc   IS NOT NULL THEN 1 ELSE 0 END) AS tieng_duc,
+  SUM(CASE WHEN tieng_nhat  IS NOT NULL THEN 1 ELSE 0 END) AS tieng_nhat,
+  SUM(CASE WHEN tieng_trung IS NOT NULL THEN 1 ELSE 0 END) AS tieng_trung
+FROM student`,
+      },
+    ],
+  },
+  {
+    category: "Hệ thống",
+    queries: [
+      {
+        label: "Schema bảng student",
+        sql: `PRAGMA table_info(student)`,
+      },
+    ],
+  },
+];
diff --git a/src/lib/subjects.js b/src/lib/subjects.js
new file mode 100644
index 0000000..d9c9dcc
--- /dev/null
+++ b/src/lib/subjects.js
@@ -0,0 +1,51 @@
+/**
+ * The 16 subject columns of the canonical schema, in display order.
+ *
+ * Mirrors `SCORE_FIELDS` in parser/src/schema.rs. Previously this list was
+ * maintained separately in score-table.jsx and student-detail.jsx, which is how
+ * they drifted out of sync with each other and with the database.
+ *
+ * No subject is dataset-specific here. Columns a given exam year has no data
+ * for are simply NULL for every row, and the UI hides all-NULL columns — so one
+ * list serves 2016 and 2017 without branching.
+ */
+
+export const SUBJECTS = [
+  { key: "toan", label: "Toán", short: "Toán" },
+  { key: "ngu_van", label: "Ngữ văn", short: "Văn" },
+  { key: "vat_ly", label: "Vật lí", short: "Lý" },
+  { key: "hoa_hoc", label: "Hóa học", short: "Hóa" },
+  { key: "sinh_hoc", label: "Sinh học", short: "Sinh" },
+  { key: "khtn", label: "KHTN", short: "KHTN" },
+  { key: "lich_su", label: "Lịch sử", short: "Sử" },
+  { key: "dia_ly", label: "Địa lí", short: "Địa" },
+  { key: "gdcd", label: "GDCD", short: "GDCD" },
+  { key: "khxh", label: "KHXH", short: "KHXH" },
+  { key: "tieng_anh", label: "Tiếng Anh", short: "T.Anh" },
+  { key: "tieng_phap", label: "Tiếng Pháp", short: "T.Pháp" },
+  { key: "tieng_nga", label: "Tiếng Nga", short: "T.Nga" },
+  { key: "tieng_duc", label: "Tiếng Đức", short: "T.Đức" },
+  { key: "tieng_nhat", label: "Tiếng Nhật", short: "T.Nhật" },
+  { key: "tieng_trung", label: "Tiếng Trung", short: "T.Trung" },
+];
+
+/**
+ * Non-score columns worth showing in the results table.
+ *
+ * Only the 2016 dataset populates these; they are NULL throughout the 2017
+ * datasets and get hidden by the same all-NULL filter that hides unused
+ * subjects, so no per-dataset conditional is needed.
+ */
+export const IDENTITY_COLUMNS = [
+  { key: "ten_cum_thi", label: "Cụm thi" },
+  { key: "gioi_tinh", label: "GT" },
+];
+
+export const SUBJECT_LABELS = Object.fromEntries(
+  SUBJECTS.map((s) => [s.key, s.label]),
+);
+
+/** True when at least one row carries a value for `key`. */
+export function hasAnyValue(rows, key) {
+  return rows.some((row) => row[key] !== null && row[key] !== undefined);
+}
diff --git a/src/router.js b/src/router.js
new file mode 100644
index 0000000..d278465
--- /dev/null
+++ b/src/router.js
@@ -0,0 +1,56 @@
+/**
+ * Path → dataset resolution.
+ *
+ * URLs are flat, one segment per dataset, and the segment IS the dataset id:
+ *
+ *   /thptqg/            → null (hub)
+ *   /thptqg/2016/       → 2016
+ *   /thptqg/2017-old/   → 2017-old
+ *
+ * That makes this an exact match on a single segment. The nested form this
+ * replaced (/thptqg/2017/old/) needed longest-prefix matching, because
+ * "/thptqg/2017/old/" also starts with "/thptqg/2017/" — an entire class of
+ * routing bug the flat scheme designs out.
+ */
+
+import { DATASETS } from "./datasets";
+
+/**
+ * URLs published before the switch to flat paths. Kept working so existing
+ * links and bookmarks resolve instead of 404ing.
+ */
+const LEGACY_PATHS = {
+  "2017/old": "2017-old",
+  "2017/old2": "2017-old2",
+};
+
+const BASE = import.meta.env.BASE_URL;
+
+/** Strip the site base and any trailing slash, leaving a bare route segment. */
+function toSegment(pathname) {
+  const path = pathname.startsWith(BASE) ? pathname.slice(BASE.length) : pathname;
+  return path.replace(/^\/+/, "").replace(/\/+$/, "");
+}
+
+/**
+ * Resolve the current location to a dataset, or null for the hub.
+ *
+ * Rewrites legacy nested URLs to their flat equivalent, preserving the query
+ * string — a `?q=` deep link must survive the redirect, which is exactly what
+ * the usual SPA 404-fallback hack would break.
+ */
+export function resolveRoute(pathname = window.location.pathname) {
+  let segment = toSegment(pathname);
+
+  const flat = LEGACY_PATHS[segment];
+  if (flat) {
+    window.history.replaceState(
+      {},
+      "",
+      `${BASE}${flat}/${window.location.search}${window.location.hash}`,
+    );
+    segment = flat;
+  }
+
+  return DATASETS.find((d) => d.id === segment) ?? null;
+}