diff --git a/apps/server/src/modules/sources-identity/service/alias-guard.ts b/apps/server/src/modules/sources-identity/service/alias-guard.ts
new file mode 100644
index 00000000..4b9948c4
--- /dev/null
+++ b/apps/server/src/modules/sources-identity/service/alias-guard.ts
@@ -0,0 +1,140 @@
+import { isGenericAliasName, normalizeTitle, type ParsedRelease, type RankedCandidate } from "@umt/domain";
+import type { Exec } from "./common.ts";
+import { addAliasIfAbsent } from "./entities.ts";
+
+// FIX-5 别名守卫:自动识别绑定后,把资源标题解析出的中 / 英文名登记为作品别名之前再过一道检查。
+// 背景:VER-4 真机《东北有个周东北》挂着《征途》等别的作品的英文名(Spark of the Long March 等),
+// 是站点标题"中文名 + 另一部作品的英文名"只靠中文名命中后,英文名被一并登记、再链式召回造成的。
+
+/** 站点名称不登记为别名的原因(记在 resolution_attempt.best.aliases.skipped) */
+export type SiteAliasSkipReason =
+  | "low_evidence"
+  | "year_conflict"
+  | "conflicts_external_title"
+  | "owned_by_other"
+  | "generic";
+
+export interface SiteAliasGuardInput {
+  /** 本次识别最佳候选的证据等级 */
+  level: string;
+  /** 候选的年份比对结果 */
+  yearMatch: string;
+  /** 资源标题解析出的年份 / 作品年份 */
+  parsedYear: number | null;
+  entityYear: number | null;
+  seasonYears?: readonly number[] | undefined;
+  /** 已归一化的站点名称与它的文字 */
+  normalized: string;
+  script: "han" | "latin";
+  /** 作品已确认的外部标题(有已接受的外部身份时:主标题 / 原标题 / TMDB 译名与别名),按文字分组,已归一化 */
+  externalNames: { han: ReadonlySet<string>; latin: ReadonlySet<string> } | null;
+  /** 这个名称已挂在别的作品上 */
+  ownedByOther: boolean;
+}
+
+export const scriptOf = (s: string): "han" | "latin" => (/\p{Script=Han}/u.test(s) ? "han" : "latin");
+
+/**
+ * 纯函数:证据等级不是最高(rule_confirmed)、年份与作品不相容、与作品已确认的同一种文字的外部标题对不上、
+ * 或已属于别的作品 → 返回不登记的原因;可以登记返回 null。
+ */
+export function siteAliasGuard(i: SiteAliasGuardInput): SiteAliasSkipReason | null {
+  if (!i.normalized || isGenericAliasName(i.normalized)) return "generic";
+  if (i.level !== "rule_confirmed") return "low_evidence";
+  if (i.yearMatch === "mismatch") return "year_conflict";
+  if (
+    i.parsedYear !== null &&
+    i.entityYear !== null &&
+    Math.abs(i.parsedYear - i.entityYear) > 1 &&
+    !(i.seasonYears ?? []).includes(i.parsedYear)
+  )
+    return "year_conflict";
+  const ext = i.externalNames?.[i.script];
+  if (ext && ext.size > 0 && !ext.has(i.normalized)) return "conflicts_external_title";
+  if (i.ownedByOther) return "owned_by_other";
+  return null;
+}
+
+/** 作品已确认的外部标题(按文字分组);没有已接受的外部身份时为 null */
+export async function confirmedExternalNames(
+  exec: Exec,
+  entityId: string,
+): Promise<{ han: Set<string>; latin: Set<string> } | null> {
+  const ident = await exec
+    .selectFrom("external_identity")
+    .select("id")
+    .where("media_entity_id", "=", entityId)
+    .where("status", "=", "accepted")
+    .executeTakeFirst();
+  if (!ident) return null;
+  const e = await exec
+    .selectFrom("media_entity")
+    .select(["title", "original_title"])
+    .where("id", "=", entityId)
+    .executeTakeFirst();
+  const aliases = await exec
+    .selectFrom("title_alias")
+    .select(["alias"])
+    .where("media_entity_id", "=", entityId)
+    .where("content_unit_id", "is", null)
+    .where("source", "=", "tmdb")
+    .execute();
+  const out = { han: new Set<string>(), latin: new Set<string>() };
+  for (const t of [e?.title, e?.original_title, ...aliases.map((a) => a.alias)]) {
+    if (!t) continue;
+    const n = normalizeTitle(t);
+    if (n) out[scriptOf(t)].add(n);
+  }
+  return out;
+}
+
+export interface SiteAliasOutcome {
+  added: string[];
+  skipped: { alias: string; reason: SiteAliasSkipReason }[];
+}
+
+/** 按守卫登记资源标题里的中 / 英文名;返回登记与跳过的清单 */
+export async function addSiteAliases(
+  exec: Exec,
+  entityId: string,
+  best: RankedCandidate,
+  parsed: ParsedRelease,
+): Promise<SiteAliasOutcome> {
+  const out: SiteAliasOutcome = { added: [], skipped: [] };
+  const names: [string, "zh" | "en"][] = [];
+  if (parsed.titleCn) names.push([parsed.titleCn, "zh"]);
+  if (parsed.titleEn) names.push([parsed.titleEn, "en"]);
+  if (!names.length) return out;
+  const entity = await exec.selectFrom("media_entity").select(["year"]).where("id", "=", entityId).executeTakeFirst();
+  const external = await confirmedExternalNames(exec, entityId);
+  for (const [t, lang] of names) {
+    const normalized = normalizeTitle(t);
+    const other = normalized
+      ? await exec
+          .selectFrom("title_alias")
+          .select("id")
+          .where("normalized", "=", normalized)
+          .where("content_unit_id", "is", null)
+          .where("media_entity_id", "<>", entityId)
+          .executeTakeFirst()
+      : undefined;
+    const reason = siteAliasGuard({
+      level: best.level,
+      yearMatch: best.yearMatch,
+      parsedYear: parsed.year ?? null,
+      entityYear: entity?.year ?? null,
+      seasonYears: best.candidate.seasonYears,
+      normalized,
+      script: scriptOf(t),
+      externalNames: external,
+      ownedByOther: !!other,
+    });
+    if (reason) {
+      if (reason !== "generic") out.skipped.push({ alias: t, reason });
+      continue;
+    }
+    await addAliasIfAbsent(exec, entityId, t, "site_title", "site", lang);
+    out.added.push(t);
+  }
+  return out;
+}
diff --git a/apps/server/src/modules/sources-identity/service/resolve.ts b/apps/server/src/modules/sources-identity/service/resolve.ts
index 70263a47..d68377e0 100644
--- a/apps/server/src/modules/sources-identity/service/resolve.ts
+++ b/apps/server/src/modules/sources-identity/service/resolve.ts
@@ -5,7 +5,6 @@ import { type SourceReleaseRow, sql } from "@umt/db";
 import {
   type IdentityCandidate as DomainCandidate,
   type IdentityResolution,
-  isGenericAliasName,
   normalizeTitle,
   PARSER_VERSION,
   type ParsedRelease,
@@ -23,11 +22,11 @@ import {
 } from "@umt/mapping";
 import { jsonb } from "../rows.ts";
 import type { SourcesRuntime } from "../runtime.ts";
+import { addSiteAliases, type SiteAliasOutcome } from "./alias-guard.ts";
 import { type Actor, closeDecisions, type Exec, SYSTEM } from "./common.ts";
 import { siteExplicitIds } from "./detail-page.ts";
 import { maybeAutoEnrich } from "./enrich.ts";
 import {
-  addAliasIfAbsent,
   createEntityFromTmdb,
   ensureUnits,
   entityByExternal,
@@ -545,16 +544,11 @@ async function bindAuto(
           .executeTakeFirstOrThrow();
         const units = await ensureUnits(trx, entityId, entity.kind, parsed);
         // 站点标题作为别名:下次同名资源可直接本地召回。只在名称本身命中过(不是仅靠别名单线命中)时登记,
-        // 且通用词(分类词 / 单字 / 停用词)不登记,避免错误别名链式扩散(ID-2)
-        if (siteAliasAllowed(best)) {
-          for (const [t, lang] of [
-            [parsed.titleCn, "zh"],
-            [parsed.titleEn, "en"],
-          ] as const) {
-            if (t && !isGenericAliasName(normalizeTitle(t)))
-              await addAliasIfAbsent(trx, entityId, t, "site_title", "site", lang);
-          }
-        }
+        // 且通用词(分类词 / 单字 / 停用词)不登记,避免错误别名链式扩散(ID-2)。
+        // FIX-5:证据等级非最高、年份不相容、与已确认外部标题冲突、已属于别的作品的名称也不登记(alias-guard.ts)
+        const aliasOutcome: SiteAliasOutcome = siteAliasAllowed(best)
+          ? await addSiteAliases(trx, entityId, best, parsed)
+          : { added: [], skipped: [] };
 
         const evidence = {
           level,
@@ -606,7 +600,10 @@ async function bindAuto(
           version,
           resolution.ranked.length,
           entityId,
-          rankedSummary(best),
+          {
+            ...rankedSummary(best),
+            ...(aliasOutcome.added.length || aliasOutcome.skipped.length ? { aliases: aliasOutcome } : {}),
+          },
         );
         await ctx.outbox.emit(
           trx,
diff --git a/apps/server/test/sources-identity/alias-guard.test.ts b/apps/server/test/sources-identity/alias-guard.test.ts
new file mode 100644
index 00000000..cdcace23
--- /dev/null
+++ b/apps/server/test/sources-identity/alias-guard.test.ts
@@ -0,0 +1,134 @@
+import { normalizeTitle } from "@umt/domain";
+import { createMockTmdb, type MockTmdb, type TmdbFixture } from "@umt/testkit";
+import { afterAll, beforeAll, describe, expect, it } from "vitest";
+import { siteAliasGuard } from "../../src/modules/sources-identity/service/alias-guard.ts";
+import { resolveRelease } from "../../src/modules/sources-identity/service/resolve.ts";
+import { createHarness, type Harness, pgAvailable, seedSite } from "./harness.ts";
+
+// FIX-5 别名守卫:站点标题里另一部作品的英文名不能挂到按中文名命中的作品上。
+
+const up = await pgAvailable();
+
+const cnTv = (id: number, zh: string, en: string | null, date: string): TmdbFixture => ({
+  type: "tv",
+  id,
+  original_title: zh,
+  original_language: "zh",
+  origin_country: ["CN"],
+  date,
+  titles: en ? { "zh-CN": zh, "en-US": en } : { "zh-CN": zh },
+  popularity: 5,
+  alternative_titles: [],
+  external_ids: {},
+});
+
+describe("siteAliasGuard(纯函数)", () => {
+  const base = {
+    level: "rule_confirmed",
+    yearMatch: "exact",
+    parsedYear: 2026,
+    entityYear: 2026,
+    normalized: "spark of the long march",
+    script: "latin" as const,
+    externalNames: null,
+    ownedByOther: false,
+  };
+  it("证据等级非最高、年份不相容、与外部标题冲突、已属于别的作品都不登记", () => {
+    expect(siteAliasGuard(base)).toBeNull();
+    expect(siteAliasGuard({ ...base, level: "multi_evidence" })).toBe("low_evidence");
+    expect(siteAliasGuard({ ...base, parsedYear: 2019 })).toBe("year_conflict");
+    expect(siteAliasGuard({ ...base, parsedYear: 2019, seasonYears: [2019] })).toBeNull();
+    expect(
+      siteAliasGuard({
+        ...base,
+        externalNames: { han: new Set(["东北有个周东北"]), latin: new Set(["zhou dongbei"]) },
+      }),
+    ).toBe("conflicts_external_title");
+    // 外部标题只有中文时,英文名不按外部标题判冲突
+    expect(siteAliasGuard({ ...base, externalNames: { han: new Set(["长河"]), latin: new Set() } })).toBeNull();
+    expect(siteAliasGuard({ ...base, ownedByOther: true })).toBe("owned_by_other");
+    expect(siteAliasGuard({ ...base, normalized: "电视剧" })).toBe("generic");
+  });
+});
+
+describe.skipIf(!up)("别名守卫(resolveObservation)", () => {
+  let h: Harness;
+  let tmdb: MockTmdb;
+  let siteId: string;
+  let n = 0;
+
+  beforeAll(async () => {
+    tmdb = await createMockTmdb({
+      fixtures: [
+        cnTv(990001, "东北有个周东北", "Zhou Dongbei in the Northeast", "2026-01-10"),
+        cnTv(990003, "长河", null, "2026-02-01"),
+      ],
+    });
+    h = await createHarness("aliasguard", { tmdbUrl: tmdb.url });
+    siteId = (await seedSite(h, { baseUrl: "https://guard.example/" })).site.id;
+    await h.db
+      .insertInto("settings")
+      .values({ key: "identity", value: JSON.stringify({ eagerTmdbLookup: true }) } as never)
+      .execute();
+  });
+  afterAll(async () => {
+    await h?.close();
+    await tmdb?.close();
+  });
+
+  const release = (title: string) =>
+    h.db
+      .insertInto("source_release")
+      .values({ site_id: siteId, site_release_id: String(880000 + ++n), title })
+      .returningAll()
+      .executeTakeFirstOrThrow();
+
+  const aliasesOf = async (entityId: string) =>
+    (
+      await h.db.selectFrom("title_alias").select(["alias", "source"]).where("media_entity_id", "=", entityId).execute()
+    ).map((a) => a.alias);
+
+  const lastAttempt = (releaseId: string) =>
+    h.db
+      .selectFrom("resolution_attempt")
+      .select(["best"])
+      .where("source_release_id", "=", releaseId)
+      .orderBy("created_at", "desc")
+      .executeTakeFirstOrThrow();
+
+  it("与作品已确认的英文名对不上的站点英文名不登记,记入 resolution_attempt", async () => {
+    const r = await release("东北有个周东北.Spark.of.the.Long.March.2026.S01E38.1080p.WEB-DL.H264-GRP");
+    const res = await resolveRelease(h.rt, { sourceReleaseId: r.id });
+    expect(res.outcome).toBe("auto");
+    const aliases = await aliasesOf(res.mediaEntityId!);
+    expect(aliases).toContain("东北有个周东北");
+    expect(aliases).not.toContain("Spark of the Long March");
+    const best = (await lastAttempt(r.id)).best as { aliases?: { skipped: { alias: string; reason: string }[] } };
+    expect(best.aliases?.skipped).toEqual([{ alias: "Spark of the Long March", reason: "conflicts_external_title" }]);
+  });
+
+  it("已属于别的作品的站点名称不登记", async () => {
+    const other = await h.db
+      .insertInto("media_entity")
+      .values({ kind: "series", title: "逆流", status: "active" } as never)
+      .returning("id")
+      .executeTakeFirstOrThrow();
+    await h.db
+      .insertInto("title_alias")
+      .values({
+        media_entity_id: other.id,
+        alias: "Against the Current",
+        normalized: normalizeTitle("Against the Current"),
+        kind: "other",
+        source: "user",
+      } as never)
+      .execute();
+    const r = await release("长河.Against.the.Current.2026.S01E01.1080p.WEB-DL.H264-GRP");
+    const res = await resolveRelease(h.rt, { sourceReleaseId: r.id });
+    expect(res.outcome).toBe("auto");
+    expect(res.mediaEntityId).not.toBe(other.id);
+    expect(await aliasesOf(res.mediaEntityId!)).not.toContain("Against the Current");
+    const best = (await lastAttempt(r.id)).best as { aliases?: { skipped: { alias: string; reason: string }[] } };
+    expect(best.aliases?.skipped).toEqual([{ alias: "Against the Current", reason: "owned_by_other" }]);
+  });
+});
diff --git a/docs/runbook/identity.md b/docs/runbook/identity.md
index f6888dce..f2043081 100644
--- a/docs/runbook/identity.md
+++ b/docs/runbook/identity.md
@@ -26,6 +26,10 @@
    交给 `domain.resolveIdentity` 打分:auto 建档 / 关联并发 `release.resolved`;否则进池。打分规则与 MP 的对照见
    `docs/porting/moviepilot-identity-match.md`(ID-2)。
 4. 自动绑定时把站点标题登记为作品别名,只在标题精确命中(或别名命中且另一种文字的名称也命中)时登记,分类词 / 单字 / 停用词不登记。
+   FIX-5 守卫(`service/alias-guard.ts`):逐个名称再查一遍,以下任一成立就不登记,原因记在 `resolution_attempt.best.aliases.skipped`
+   (`added` 是登记了的):证据等级不是 `rule_confirmed`(`low_evidence`);资源年份与作品年份差超过 1 年且不是季年份(`year_conflict`);
+   作品有已接受的外部身份,且同一种文字(中文 / 拉丁)下已有确认的外部标题(主标题 / 原标题 / TMDB 译名与别名),这个名称对不上
+   (`conflicts_external_title`);这个名称已经挂在别的作品上(`owned_by_other`)。
 
 标题更新(RSS 标题与列表标题不同、站点改标题):按新标题重新解析,发 `release.observed(isNew=false)`,以 `force` 重新识别
 (已识别的也不短路,触发来源仍是 observed);重新识别不能确认时撤销原自动绑定、进池。人工锁定的不动。
@@ -99,6 +103,24 @@ DATABASE_URL=postgres://umt:<密码>@$PGIP:5432/umt deno run -A scripts/identity
   `resolution_attempt(outcome = manual, reason = rollback_wrong_alias)`。内容单元不删,只报告无资源引用的数量;引用了这些资源的其他表只报告。
 - 2026-09-29 用户库副本演练:《东北有个周东北》29 条绑定里 23 条误并入,删除 7 个站点别名(「电视剧」「动漫」「综艺」与 4 个链式英文名)。
 
+## 冲突别名与临时内容单元清理(FIX-5,`scripts/identity-cleanup.ts`)
+
+守卫上线前登记的错误别名、重复 / 孤立的临时内容单元用这个脚本清理。缺省只读,`--apply` 在一个事务里执行并写审计
+`identity.cleanup`;`--keep-orphans` 不删孤立单元;`--entity <id>` 只处理一部作品。连接方式同上。
+
+```sh
+DATABASE_URL=postgres://umt:<密码>@$PGIP:5432/umt deno run -A scripts/identity-cleanup.ts            # 看清单
+DATABASE_URL=postgres://umt:<密码>@$PGIP:5432/umt deno run -A scripts/identity-cleanup.ts --apply    # 确认后执行
+```
+
+- 冲突别名:只动 `source = site` 的作品级别名,且不是作品自己的名字(主标题 / 原标题 / TMDB 别名)。同一归一化别名还挂在别的作品上
+  (或是别的作品的标题)→ 删;作品有已接受外部身份、同一种文字下已有确认外部标题而它对不上 → 删(中文标题的拼音写法保留);
+  本作品下带这个名字的资源都解析出年份且都与作品年份差超过 1 年 → 删。
+- 重复的临时内容单元:同作品同类型同季同集号(未退役)有多条且有临时的,保留被引用最多的(同数时 confirmed 优先、再取最早的),
+  其余的引用改指向保留的那条(撞唯一约束的元数据行直接删),子单元改挂,然后删除。
+- 孤立的临时内容单元:`provisional`、没有资源 / 资产 / 订阅 / 下载 / 整理等任何引用、没有 TMDB 来源字段(不是 TMDB 已知的集)、
+  没有保留的子单元 → 删除(字段来源 / 覆盖 / 单元别名一并删)。TMDB 已知的集即使没有资源也保留。
+
 ## 排查
 
 ```sql
diff --git a/scripts/identity-cleanup.ts b/scripts/identity-cleanup.ts
new file mode 100644
index 00000000..1c5657a7
--- /dev/null
+++ b/scripts/identity-cleanup.ts
@@ -0,0 +1,377 @@
+// 身份数据清理(FIX-5):删除冲突别名、合并重复的临时内容单元、删除孤立的临时内容单元。默认只读(dry-run),加 --apply 才改库。
+//
+// 用法(DATABASE_URL 必须显式给出,脚本不带默认库):
+//   DATABASE_URL=postgres://umt:***@<host>:5432/umt deno run -A scripts/identity-cleanup.ts                 # 看清单
+//   DATABASE_URL=… deno run -A scripts/identity-cleanup.ts --apply                                          # 执行(单个事务)
+//   DATABASE_URL=… deno run -A scripts/identity-cleanup.ts --keep-orphans                                   # 不删孤立单元
+//   DATABASE_URL=… deno run -A scripts/identity-cleanup.ts --entity <作品 id>                              # 只看 / 只处理一部作品
+//
+// 1. 冲突别名:只处理自动识别登记的站点别名(title_alias.source = 'site',作品级)。以下任一成立即删除:
+//    - shared:同一归一化别名还挂在别的作品上,且它不是本作品自己的名字(主标题 / 原标题 / TMDB 译名与别名);
+//    - script:作品有已接受的外部身份,且同一种文字(中文 / 拉丁)下已有确认的外部标题,这个别名对不上任何一个
+//      (中文标题的拼音写法视为相容,保留);
+//    - year:本作品下带这个名字的资源都解析出了年份,且都与作品年份相差超过 1 年。
+// 2. 重复的临时内容单元:同一作品、同一类型、同季同集号有多条(未退役)且至少一条是临时(provisional)的,
+//    保留被引用最多的那条(同数时 confirmed 优先,再取最早建的),其余的引用改指向保留的那条后删除;
+//    改指向会撞唯一约束的行(同一字段来源 / 别名已在保留的单元上)直接删掉。
+// 3. 孤立的临时内容单元(--keep-orphans 跳过):provisional、没有任何资源 / 资产 / 订阅 / 下载 / 整理等引用、
+//    没有 TMDB 来源的字段(不是 TMDB 已知的季 / 集)、也没有子单元的,删除;字段来源 / 覆盖 / 单元别名随之删除。
+// --apply 在一个事务里执行,并写一条审计事件(action = identity.cleanup)。
+
+import { normalizeTitle, parseRelease } from "@umt/domain";
+import pg from "pg";
+
+const argv = [...Deno.args];
+const APPLY = argv.includes("--apply");
+const KEEP_ORPHANS = argv.includes("--keep-orphans");
+const entityArg = argv.indexOf("--entity");
+const ONLY_ENTITY = entityArg >= 0 ? (argv[entityArg + 1] ?? null) : null;
+const url = Deno.env.get("DATABASE_URL");
+if (!url) {
+  console.error("需要 DATABASE_URL(脚本不带默认库)");
+  Deno.exit(2);
+}
+const db = new pg.Client({ connectionString: url });
+await db.connect();
+const q = async <T>(text: string, values: unknown[] = []) => (await db.query(text, values)).rows as T[];
+console.log(`# identity-cleanup (${APPLY ? "APPLY" : "DRY-RUN"})${KEEP_ORPHANS ? " --keep-orphans" : ""}\n`);
+
+const isHan = (s: string) => /\p{Script=Han}/u.test(s);
+
+// ---------------------------------------------------------------- 拼音判断(中文标题的拉丁写法视为相容)
+const SYLLABLE =
+  /^(?:(?:zh|ch|sh|[bpmfdtnlgkhjqxrzcsyw])?(?:iang|iong|uang|ueng|ang|eng|ing|ong|iao|ian|uai|uan|van|ai|ei|ui|ao|ou|iu|ie|ve|ue|er|an|en|in|un|vn|ia|ua|uo|a|o|e|i|u|v))$/;
+/** 全部由拼音音节组成(允许音节连写,如 Dongbei) */
+function looksLikePinyin(text: string): boolean {
+  const words = text
+    .toLowerCase()
+    .replace(/[^a-z\s'-]/g, " ")
+    .split(/[\s'-]+/)
+    .filter(Boolean);
+  if (!words.length || /[^a-z\s'-]/i.test(text.replace(/[\s\d.:,!?·]/g, ""))) return false;
+  const seg = (w: string): boolean => {
+    if (!w) return true;
+    for (let k = Math.min(6, w.length); k >= 1; k--) if (SYLLABLE.test(w.slice(0, k)) && seg(w.slice(k))) return true;
+    return false;
+  };
+  return words.every(seg);
+}
+
+// ---------------------------------------------------------------- 1. 冲突别名
+interface AliasRow {
+  id: string;
+  media_entity_id: string;
+  alias: string;
+  normalized: string;
+  source: string;
+}
+interface EntityRow {
+  id: string;
+  title: string;
+  original_title: string | null;
+  year: number | null;
+  confirmed: boolean;
+}
+const entityFilter = ONLY_ENTITY ? "and a.media_entity_id = $1" : "";
+const entityVals = ONLY_ENTITY ? [ONLY_ENTITY] : [];
+const siteAliases = await q<AliasRow>(
+  `select a.id, a.media_entity_id, a.alias, a.normalized, a.source from title_alias a
+    where a.source = 'site' and a.content_unit_id is null ${entityFilter}`,
+  entityVals,
+);
+const entityIds = [...new Set(siteAliases.map((a) => a.media_entity_id))];
+const entities = new Map(
+  (
+    await q<EntityRow>(
+      `select e.id, e.title, e.original_title, e.year,
+              exists(select 1 from external_identity x where x.media_entity_id = e.id and x.status = 'accepted') as confirmed
+         from media_entity e where e.id = any($1::uuid[])`,
+      [entityIds],
+    )
+  ).map((e) => [e.id, e]),
+);
+const tmdbAliases = await q<{ media_entity_id: string; alias: string }>(
+  `select media_entity_id, alias from title_alias where source = 'tmdb' and content_unit_id is null
+     and media_entity_id = any($1::uuid[])`,
+  [entityIds],
+);
+/** 作品自己的名字(归一化),按文字分组 */
+const ownNames = new Map<string, { han: Set<string>; latin: Set<string> }>();
+for (const e of entities.values()) {
+  const own = { han: new Set<string>(), latin: new Set<string>() };
+  for (const t of [
+    e.title,
+    e.original_title,
+    ...tmdbAliases.filter((a) => a.media_entity_id === e.id).map((a) => a.alias),
+  ])
+    if (t) {
+      const n = normalizeTitle(t);
+      if (n) own[isHan(t) ? "han" : "latin"].add(n);
+    }
+  ownNames.set(e.id, own);
+}
+const shared = new Map<string, Set<string>>();
+for (const r of await q<{ normalized: string; media_entity_id: string }>(
+  `select distinct a.normalized, a.media_entity_id from title_alias a join media_entity e on e.id = a.media_entity_id
+    where a.content_unit_id is null and e.status <> 'merged' and a.normalized = any($1::text[])`,
+  [[...new Set(siteAliases.map((a) => a.normalized))]],
+)) {
+  const s = shared.get(r.normalized) ?? new Set<string>();
+  s.add(r.media_entity_id);
+  shared.set(r.normalized, s);
+}
+// 同名作品的主标题也算"别的作品的名字"
+for (const r of await q<{ id: string; title: string; original_title: string | null }>(
+  `select id, title, original_title from media_entity where status <> 'merged'`,
+)) {
+  for (const t of [r.title, r.original_title]) {
+    if (!t) continue;
+    const n = normalizeTitle(t);
+    const s = shared.get(n);
+    if (s) s.add(r.id);
+  }
+}
+const releasesByEntity = new Map<string, { title: string; subtitle: string | null }[]>();
+for (const r of await q<{ media_entity_id: string; title: string; subtitle: string | null }>(
+  `select media_entity_id, title, subtitle from source_release where media_entity_id = any($1::uuid[])`,
+  [entityIds],
+)) {
+  const l = releasesByEntity.get(r.media_entity_id) ?? [];
+  l.push(r);
+  releasesByEntity.set(r.media_entity_id, l);
+}
+
+type AliasReason = "shared" | "script" | "year";
+const aliasDeletes: (AliasRow & { reason: AliasReason; others?: string[] })[] = [];
+for (const a of siteAliases) {
+  const e = entities.get(a.media_entity_id);
+  if (!e) continue;
+  const own = ownNames.get(e.id)!;
+  const n = normalizeTitle(a.alias) || a.normalized;
+  const script = isHan(a.alias) ? "han" : "latin";
+  if (own.han.has(n) || own.latin.has(n)) continue;
+  const others = [...(shared.get(a.normalized) ?? [])].filter((id) => id !== e.id);
+  if (others.length) {
+    aliasDeletes.push({ ...a, reason: "shared", others });
+    continue;
+  }
+  if (e.confirmed && own[script].size > 0 && !(script === "latin" && looksLikePinyin(a.alias))) {
+    aliasDeletes.push({ ...a, reason: "script" });
+    continue;
+  }
+  if (e.year !== null) {
+    const years = (releasesByEntity.get(e.id) ?? [])
+      .map((r) => parseRelease(r.title, r.subtitle ? { subtitle: r.subtitle } : {}))
+      .filter((p) => [p.titleCn, p.titleEn, p.title].some((t) => t && normalizeTitle(t) === n))
+      .map((p) => p.year ?? null);
+    if (years.length && years.every((y) => y !== null && Math.abs(y - e.year!) > 1))
+      aliasDeletes.push({ ...a, reason: "year" });
+  }
+}
+const REASON_TEXT: Record<AliasReason, string> = {
+  shared: "同名别名挂在别的作品上",
+  script: "与已确认的外部标题对不上",
+  year: "带这个名字的资源年份都与作品不符",
+};
+const entityTitle = async (id: string) =>
+  entities.get(id)?.title ??
+  (await q<{ title: string }>(`select title from media_entity where id = $1`, [id]))[0]?.title ??
+  id;
+console.log(`## 冲突别名:${aliasDeletes.length} 个`);
+for (const eid of [...new Set(aliasDeletes.map((a) => a.media_entity_id))]) {
+  const e = entities.get(eid)!;
+  console.log(`\n### ${e.title}(${e.year ?? "-"}) ${eid}`);
+  for (const a of aliasDeletes.filter((x) => x.media_entity_id === eid)) {
+    const also = a.others?.length
+      ? `:${(await Promise.all(a.others.slice(0, 3).map(entityTitle))).map((t) => `《${t}》`).join("")}`
+      : "";
+    console.log(`  - 删除「${a.alias}」(${REASON_TEXT[a.reason]}${also})`);
+  }
+}
+
+// ---------------------------------------------------------------- 引用 content_unit 的表
+interface FkRef {
+  table: string;
+  column: string;
+}
+const fks = await q<FkRef>(
+  `select c.conrelid::regclass::text as table, a.attname as column
+     from pg_constraint c
+     join pg_attribute a on a.attrelid = c.conrelid and a.attnum = any(c.conkey)
+    where c.contype = 'f' and c.confrelid = 'content_unit'::regclass`,
+);
+/** 只是单元自身的元数据(随单元删除),不算"被使用" */
+const META_TABLES = new Set(["metadata_field", "field_override", "title_alias"]);
+const usageRefs = fks.filter((f) => !META_TABLES.has(f.table.replace(/^.*\./, "")) && f.table !== "content_unit");
+const quoteIdent = (s: string) =>
+  s
+    .split(".")
+    .map((p) => `"${p.replace(/"/g, '""')}"`)
+    .join(".");
+async function refCounts(ids: string[]): Promise<Map<string, number>> {
+  const out = new Map<string, number>(ids.map((id) => [id, 0]));
+  if (!ids.length) return out;
+  for (const f of usageRefs) {
+    const rows = await q<{ id: string; n: number }>(
+      `select ${quoteIdent(f.column)} as id, count(*)::int as n from ${quoteIdent(f.table)}
+        where ${quoteIdent(f.column)} = any($1::uuid[]) group by 1`,
+      [ids],
+    );
+    for (const r of rows) out.set(r.id, (out.get(r.id) ?? 0) + r.n);
+  }
+  return out;
+}
+
+// ---------------------------------------------------------------- 2. 重复的临时内容单元
+interface UnitRow {
+  id: string;
+  media_entity_id: string;
+  kind: string;
+  season_number: number | null;
+  episode_number: number | null;
+  status: string;
+  created_at: Date;
+}
+const unitFilter = ONLY_ENTITY ? "and u.media_entity_id = $1" : "";
+const dupRows = await q<UnitRow>(
+  `select u.id, u.media_entity_id, u.kind, u.season_number, u.episode_number, u.status, u.created_at
+     from content_unit u
+     join (select media_entity_id, kind, season_number, episode_number from content_unit
+            where status <> 'retired' group by 1, 2, 3, 4
+           having count(*) > 1 and bool_or(status = 'provisional')) g
+       on g.media_entity_id = u.media_entity_id and g.kind = u.kind
+      and g.season_number is not distinct from u.season_number and g.episode_number is not distinct from u.episode_number
+    where u.status <> 'retired' ${unitFilter}
+    order by u.media_entity_id, u.season_number, u.episode_number, u.created_at`,
+  ONLY_ENTITY ? [ONLY_ENTITY] : [],
+);
+const dupRefs = await refCounts(dupRows.map((u) => u.id));
+const groups = new Map<string, UnitRow[]>();
+for (const u of dupRows) {
+  const k = `${u.media_entity_id}|${u.kind}|${u.season_number}|${u.episode_number}`;
+  groups.set(k, [...(groups.get(k) ?? []), u]);
+}
+const merges: { keep: UnitRow; drop: UnitRow[] }[] = [];
+for (const list of groups.values()) {
+  const sorted = [...list].sort(
+    (a, b) =>
+      (dupRefs.get(b.id) ?? 0) - (dupRefs.get(a.id) ?? 0) ||
+      Number(b.status === "confirmed") - Number(a.status === "confirmed") ||
+      new Date(a.created_at).getTime() - new Date(b.created_at).getTime(),
+  );
+  merges.push({ keep: sorted[0]!, drop: sorted.slice(1) });
+}
+const unitLabel = (u: Pick<UnitRow, "kind" | "season_number" | "episode_number">) =>
+  u.kind === "season"
+    ? `S${String(u.season_number ?? 0).padStart(2, "0")}`
+    : `S${String(u.season_number ?? 0).padStart(2, "0")}E${String(u.episode_number ?? 0).padStart(2, "0")}`;
+console.log(`\n## 重复的临时内容单元:${merges.length} 组,删除 ${merges.reduce((s, m) => s + m.drop.length, 0)} 条`);
+for (const m of merges) {
+  console.log(
+    `  - 《${await entityTitle(m.keep.media_entity_id)}》${unitLabel(m.keep)}:保留 ${m.keep.id}(${m.keep.status},引用 ${dupRefs.get(m.keep.id) ?? 0}),` +
+      `合并 ${m.drop.map((d) => `${d.id}(${d.status},引用 ${dupRefs.get(d.id) ?? 0})`).join("、")}`,
+  );
+}
+
+// ---------------------------------------------------------------- 3. 孤立的临时内容单元
+const dropping = new Set(merges.flatMap((m) => m.drop.map((d) => d.id)));
+let orphans: UnitRow[] = [];
+if (!KEEP_ORPHANS) {
+  const cand = await q<UnitRow>(
+    `select u.id, u.media_entity_id, u.kind, u.season_number, u.episode_number, u.status, u.created_at
+       from content_unit u
+      where u.status = 'provisional' ${unitFilter}
+        and not exists (select 1 from metadata_field f where f.content_unit_id = u.id and f.source = 'tmdb')
+      order by u.media_entity_id, u.kind desc, u.season_number, u.episode_number`,
+    ONLY_ENTITY ? [ONLY_ENTITY] : [],
+  );
+  const refs = await refCounts(cand.map((u) => u.id));
+  const unused = cand.filter((u) => (refs.get(u.id) ?? 0) === 0 && !dropping.has(u.id));
+  const unusedIds = new Set(unused.map((u) => u.id));
+  // 季单元:子单元全都要删(或没有子单元)才删
+  const children = await q<{ parent_unit_id: string; id: string }>(
+    `select parent_unit_id, id from content_unit where parent_unit_id = any($1::uuid[])`,
+    [unused.filter((u) => u.kind === "season").map((u) => u.id)],
+  );
+  orphans = unused.filter(
+    (u) =>
+      u.kind !== "season" ||
+      children.filter((c) => c.parent_unit_id === u.id).every((c) => unusedIds.has(c.id) || dropping.has(c.id)),
+  );
+  console.log(`\n## 孤立的临时内容单元:${orphans.length} 条`);
+  const byEntity = new Map<string, UnitRow[]>();
+  for (const u of orphans) byEntity.set(u.media_entity_id, [...(byEntity.get(u.media_entity_id) ?? []), u]);
+  for (const [eid, list] of byEntity) console.log(`  - 《${await entityTitle(eid)}》:${list.map(unitLabel).join(" ")}`);
+} else console.log("\n## 孤立的临时内容单元:跳过(--keep-orphans)");
+
+// ---------------------------------------------------------------- 执行
+if (APPLY) {
+  await db.query("begin");
+  try {
+    if (aliasDeletes.length)
+      await q(`delete from title_alias where id = any($1::uuid[])`, [aliasDeletes.map((a) => a.id)]);
+    let repointed = 0;
+    let droppedRows = 0;
+    const allRefTables = fks.filter((f) => f.table !== "content_unit");
+    for (const m of merges) {
+      for (const d of m.drop) {
+        for (const f of allRefTables) {
+          const rows = await q<{ ctid: string }>(
+            `select ctid::text from ${quoteIdent(f.table)} where ${quoteIdent(f.column)} = $1`,
+            [d.id],
+          );
+          for (const r of rows) {
+            await db.query("savepoint sp");
+            try {
+              await q(`update ${quoteIdent(f.table)} set ${quoteIdent(f.column)} = $1 where ctid = $2::tid`, [
+                m.keep.id,
+                r.ctid,
+              ]);
+              await db.query("release savepoint sp");
+              repointed++;
+            } catch (e) {
+              await db.query("rollback to savepoint sp");
+              if ((e as { code?: string }).code !== "23505") throw e;
+              await q(`delete from ${quoteIdent(f.table)} where ctid = $1::tid`, [r.ctid]);
+              droppedRows++;
+            }
+          }
+        }
+        await q(`update content_unit set parent_unit_id = $1 where parent_unit_id = $2`, [m.keep.id, d.id]);
+        await q(`delete from content_unit where id = $1`, [d.id]);
+      }
+    }
+    // 孤立单元:先集后季
+    const orphanIds = orphans
+      .sort((a, b) => Number(a.kind === "season") - Number(b.kind === "season"))
+      .map((u) => u.id);
+    for (const t of META_TABLES)
+      if (fks.some((f) => f.table.replace(/^.*\./, "") === t))
+        await q(`delete from ${quoteIdent(t)} where content_unit_id = any($1::uuid[])`, [orphanIds]);
+    for (const u of orphans.filter((x) => x.kind !== "season"))
+      await q(`delete from content_unit where id = $1`, [u.id]);
+    for (const u of orphans.filter((x) => x.kind === "season"))
+      await q(`delete from content_unit where id = $1`, [u.id]);
+    await q(
+      `insert into audit_event (actor_type, actor_id, action, target_type, target_id, payload)
+       values ('system', 'identity-cleanup', 'identity.cleanup', 'media_entity', $1, $2::jsonb)`,
+      [
+        ONLY_ENTITY,
+        JSON.stringify({
+          aliases: aliasDeletes.map((a) => ({ entityId: a.media_entity_id, alias: a.alias, reason: a.reason })),
+          mergedUnits: merges.map((m) => ({ keep: m.keep.id, drop: m.drop.map((d) => d.id) })),
+          orphanUnits: orphans.length,
+        }),
+      ],
+    );
+    await db.query("commit");
+    console.log(
+      `\n已执行:删除 ${aliasDeletes.length} 个别名;合并 ${dropping.size} 个重复单元(改指向 ${repointed} 行,删除冲突行 ${droppedRows} 行);` +
+        `删除 ${orphans.length} 个孤立单元`,
+    );
+  } catch (e) {
+    await db.query("rollback");
+    throw e;
+  }
+} else console.log("\n(dry-run:未改库;确认后加 --apply 执行)");
+await db.end();