diff --git a/backend/app/auth/access.py b/backend/app/auth/access.py
index 3c04db08..07eda877 100644
--- a/backend/app/auth/access.py
+++ b/backend/app/auth/access.py
@@ -62,6 +62,7 @@ def hidden_runs(principal: Any) -> Any:
     from app.db.models import Run
     from app.db.models_apps import App
     from app.db.models_blueprints import Blueprint
+    from app.db.portable import json_text
 
     if principal.mode == "off":
         return false()
@@ -72,7 +73,7 @@ def hidden_runs(principal: Any) -> Any:
     kind = func.coalesce(Run.origin_kind, "")
     return or_(
         and_(kind == "personal_app", or_(Run.app_id.is_(None), Run.app_id.not_in(mine))),
-        and_(kind == "trial", func.coalesce(func.json_extract(Run.origin, "$.blueprint_id"), "").in_(others)),
+        and_(kind == "trial", func.coalesce(json_text(Run.origin, "blueprint_id"), "").in_(others)),
     )
 
 
diff --git a/backend/app/auth/keys.py b/backend/app/auth/keys.py
index 1d4c5dc3..5f228c6c 100644
--- a/backend/app/auth/keys.py
+++ b/backend/app/auth/keys.py
@@ -39,7 +39,7 @@ from dataclasses import dataclass
 from datetime import datetime, timedelta, timezone
 from typing import Any, Awaitable, Callable
 
-from sqlalchemy import delete, func, select
+from sqlalchemy import delete, select
 from starlette.requests import HTTPConnection
 
 from app.api.coded import CodedHTTPException
@@ -535,12 +535,13 @@ async def started_before(principal: Any, idem_key: str) -> str | None:
     """拥有者按这个幂等键用密钥发起过的实例（来源里记着 idempotency_key）：处理到一半服务停了、同一个键重新认领时交回它。"""
     from app.db.base import SessionLocal
     from app.db.models import Run
+    from app.db.portable import json_eq
 
     async with SessionLocal() as session:
         return await session.scalar(select(Run.id).where(
             Run.origin_kind == "app_entry", Run.started_by == principal.username,
-            func.json_extract(Run.origin, "$.idempotency_key") == idem_key,
-            func.json_extract(Run.origin, "$.via") == "key").order_by(Run.created_at.desc()).limit(1))
+            json_eq(Run.origin, "idempotency_key", idem_key),
+            json_eq(Run.origin, "via", "key")).order_by(Run.created_at.desc()).limit(1))
 
 
 # ---------------------------------------------------------------- 请求记录（A6）
diff --git a/backend/app/blueprints/personal.py b/backend/app/blueprints/personal.py
index 4c73a020..770d5864 100644
--- a/backend/app/blueprints/personal.py
+++ b/backend/app/blueprints/personal.py
@@ -416,9 +416,10 @@ async def refresh(session: AsyncSession, app: Any, *, principal: Any) -> tuple[A
 
 def _runs_of(app_id: str, graph_hash: str) -> Any:
     from app.db.models import Run
+    from app.db.portable import json_eq
 
     return select(Run).where(Run.app_id == app_id, Run.origin_kind == ORIGIN,
-                             func.json_extract(Run.origin, "$.graph_hash") == graph_hash)
+                             json_eq(Run.origin, "graph_hash", graph_hash))
 
 
 async def latest_refresh(session: AsyncSession, app_id: str, graph_hash: str, *, active_only: bool = False) -> Any:
diff --git a/backend/app/capabilities/registry.py b/backend/app/capabilities/registry.py
index ea63d849..77a49d13 100644
--- a/backend/app/capabilities/registry.py
+++ b/backend/app/capabilities/registry.py
@@ -127,10 +127,9 @@ async def _discover(session: AsyncSession) -> dict[str, dict[str, Any]]:
 
 async def sync_all(session: AsyncSession) -> int:
     """把内置工具、数据源、自定义工具、MCP 同步进 capabilities。返回变动的行数。启动时和各对象增删改时调。"""
-    from sqlalchemy.dialects.sqlite import insert
-
     from app.db.base import utcnow
     from app.db.models import Capability
+    from app.db.portable import insert_ignore
 
     found = await _discover(session)
     existing = {row.name: row for row in (await session.execute(select(Capability))).scalars()}
@@ -169,8 +168,10 @@ async def sync_all(session: AsyncSession) -> int:
             row.synced_at = now
             changed += 1
     if fresh:
-        # 两个请求同时同步（列表页和发起运行撞在一起）：后到的那条插入什么都不做，不报主键冲突。不加锁（单进程 + SQLite）
-        done = await session.execute(insert(Capability).values(fresh).on_conflict_do_nothing(index_elements=["name"]))
+        # 两个请求同时同步（列表页和发起运行撞在一起）：后到的那条插入什么都不做，不报主键冲突。不加锁：两种库都是同一条
+        # INSERT … ON CONFLICT DO NOTHING，多个进程同时同步也一样
+        done = await session.execute(
+            insert_ignore(session, Capability).values(fresh).on_conflict_do_nothing(index_elements=["name"]))
         changed += done.rowcount or 0
     if changed or fresh:
         await session.commit()
diff --git a/backend/app/chat/questions.py b/backend/app/chat/questions.py
index 99d61240..54d56f50 100644
--- a/backend/app/chat/questions.py
+++ b/backend/app/chat/questions.py
@@ -98,6 +98,7 @@ async def recent_questions(session: AsyncSession, principal: Any, *, limit: int)
     """最近问过的问题，从新到旧，最多 limit 条（取法见模块开头）。principal 用来去掉这个人读不了的只给拥有者的运行。"""
     from app.auth.access import hidden_runs
     from app.db.models import Conversation, ConversationTurn, Run
+    from app.db.portable import json_is_string
     from app.engine.origin import counted_runs
 
     hidden = hidden_runs(principal)
@@ -112,7 +113,7 @@ async def recent_questions(session: AsyncSession, principal: Any, *, limit: int)
     runs = (await session.execute(
         select(Run.id, Run.input, Run.workflow_name, Run.created_at, Run.origin_kind)
         .where(Run.run_class != "formal", func.coalesce(Run.origin_kind, "") != "chat", counted_runs(), not_(hidden),
-               func.json_type(Run.input, "$.question") == "text")
+               json_is_string(Run.input, "question"))
         .order_by(Run.created_at.desc()).limit(limit)
     )).all()
     out = [Question(text=question.strip(), at=at, run_id=run_id, turn_id=turn_id, workflow=workflow, origin="chat")
diff --git a/backend/app/core/config.py b/backend/app/core/config.py
index 955e7242..2ddb6629 100644
--- a/backend/app/core/config.py
+++ b/backend/app/core/config.py
@@ -47,6 +47,17 @@ class Settings(BaseSettings):
 
     # --- 存储 ---
     data_dir: Path = PROJECT_DIR / "data"
+    # 应用自己的库（工作流、运行、事件、审批……）。不设：数据目录里的 SQLite（agentlab.db，断点在 checkpoints.db），
+    # 单机单进程。设成 postgresql+asyncpg://用户:密码@主机:端口/库名（postgresql:// 也认）时整个应用库用 PostgreSQL，
+    # LangGraph 的断点也放进同一个库；checkpoint_url 另给就放那里。数据目录照旧要有：工件、上传表格、沙箱等仍是文件
+    database_url: str = ""
+    checkpoint_url: str = ""
+    # PostgreSQL 的连接池（SQLite 不用这几项）。pool_size=0 表示不用连接池、每次新建连接（前面有 PgBouncer 时用，
+    # 测试里也这么用：每个测试一个事件循环，asyncpg 的连接不能跨循环）
+    db_pool_size: int = 10
+    db_max_overflow: int = 20
+    db_pool_timeout: int = 30
+    db_pool_recycle: int = 1800
 
     # --- 前端构建产物（生产部署用）---
     # 设了就由服务端一并托管页面（见 app/web.py），页面和接口同源、只起一个进程。
@@ -195,6 +206,23 @@ class Settings(BaseSettings):
             return True
         return value
 
+    @field_validator("database_url", "checkpoint_url", mode="before")
+    @classmethod
+    def _valid_postgres_url(cls, value: object, info: Any) -> object:
+        # 写错了启动时就报出来，别等到第一次查库。只认 PostgreSQL：SQLite 就是不设
+        if value is None or (isinstance(value, str) and not value.strip()):
+            return ""
+        if not isinstance(value, str):
+            return value
+        from app.db.urls import normalize_database_url, normalize_checkpoint_url
+
+        name = f"AGENTLAB_{(info.field_name or '').upper()}"
+        normalize = normalize_database_url if info.field_name == "database_url" else normalize_checkpoint_url
+        try:
+            return normalize(value.strip())
+        except ValueError as e:
+            raise ValueError(f"{name}：{e}") from None
+
     @field_validator("web_dist", mode="before")
     @classmethod
     def _blank_is_unset(cls, value: object) -> object:
@@ -223,13 +251,30 @@ class Settings(BaseSettings):
 
     @property
     def db_url(self) -> str:
-        return f"sqlite+aiosqlite:///{self.db_path}"
+        """应用库的 SQLAlchemy 地址：设了 database_url 用它（已规范成 postgresql+asyncpg://），否则数据目录里的 SQLite。"""
+        return self.database_url or f"sqlite+aiosqlite:///{self.db_path}"
+
+    @property
+    def db_dialect(self) -> str:
+        """"sqlite" 或 "postgresql"。"""
+        return "postgresql" if self.database_url else "sqlite"
 
     @property
     def checkpoint_path(self) -> Path:
-        """LangGraph checkpointer 用独立的库文件，避免和业务表抢写锁。"""
+        """LangGraph checkpointer 用独立的库文件，避免和业务表抢写锁。只在 SQLite 时用。"""
         return self.data_dir / "checkpoints.db"
 
+    @property
+    def checkpoint_conninfo(self) -> str | None:
+        """PostgreSQL 断点库的 libpq 连接串（psycopg 用）：checkpoint_url 优先，否则由 database_url 换算。SQLite 时 None。"""
+        if self.checkpoint_url:
+            return self.checkpoint_url
+        if self.database_url:
+            from app.db.urls import libpq_conninfo
+
+            return libpq_conninfo(self.database_url)
+        return None
+
     @property
     def workspace_dir(self) -> Path:
         """沙箱与文件工具的可写根目录，一切文件访问都被限制在这里面。"""
diff --git a/backend/app/data/capability_review.py b/backend/app/data/capability_review.py
index 3db355c0..9751f4e3 100644
--- a/backend/app/data/capability_review.py
+++ b/backend/app/data/capability_review.py
@@ -144,10 +144,18 @@ def normalize_fields(existing: Mapping[str, Any] | None, submitted: Any, *, at:
 
 async def run_counts(session: AsyncSession) -> dict[str, int]:
     """每项能力被几次运行用到：{能力名: 运行次数}，没用过的不出现。按运行发起时记下的能力治理快照数
-    （Run.options["capabilities"]，一次运行里一项能力只记一次）。只用 SQLite 的 json_each，一次查询。"""
-    rows = await session.execute(text(
-        "SELECT j.key, COUNT(*) FROM runs, json_each(runs.options, '$.capabilities') AS j "
-        "WHERE json_valid(runs.options) GROUP BY j.key"))
+    （Run.options["capabilities"]，一次运行里一项能力只记一次）。一次查询：两种库都用 json_each（PostgreSQL 的碰到不是
+    对象的值会报错，先按类型挑出来）。"""
+    from app.db.portable import dialect_of
+
+    if dialect_of(session) == "postgresql":
+        sql = ("SELECT j.key, COUNT(*) FROM runs CROSS JOIN LATERAL json_each(CASE WHEN "
+               "json_typeof(runs.options -> 'capabilities') = 'object' THEN runs.options -> 'capabilities' "
+               "ELSE '{}'::json END) AS j GROUP BY j.key")
+    else:
+        sql = ("SELECT j.key, COUNT(*) FROM runs, json_each(runs.options, '$.capabilities') AS j "
+               "WHERE json_valid(runs.options) GROUP BY j.key")
+    rows = await session.execute(text(sql))
     return {str(name): int(count) for name, count in rows.all()}
 
 
diff --git a/backend/app/data/catalog_profile_jobs.py b/backend/app/data/catalog_profile_jobs.py
index 37a4b097..810c3758 100644
--- a/backend/app/data/catalog_profile_jobs.py
+++ b/backend/app/data/catalog_profile_jobs.py
@@ -48,7 +48,7 @@ import logging
 import time
 from typing import Any
 
-from sqlalchemy import case, delete, func, or_, select, update
+from sqlalchemy import case, delete, func, not_, or_, select, update
 from sqlalchemy.exc import IntegrityError
 from sqlalchemy.ext.asyncio import AsyncSession
 
@@ -60,6 +60,7 @@ from app.data.catalog_profile import (
 )
 from app.data.engine import SnapshotTampered
 from app.db.base import SessionLocal, new_id, utcnow
+from app.db.portable import json_flag
 from app.db.models import CatalogDraftJob, CatalogProfileJob, CatalogProfileTask, DataSource
 
 logger = logging.getLogger(__name__)
@@ -345,7 +346,7 @@ _SHOWN = (case((CatalogProfileTask.started_at.is_(None), 1), else_=0), *_NEWEST)
 #: 只做了取值观察的那一项（observe 范围、maintenance 范围里只到期观察的表）在逐表一行的 summary 里带这个标记：它不是一次
 #: 剖析，不算「上次剖析」——不然表清单的「上次剖析」、给助手的剖析事实（行数、日期范围）会被一次只记了行数的观察顶掉
 OBSERVE_ONLY = "observe_only"
-_PROFILED = func.coalesce(func.json_extract(CatalogProfileTask.summary, f"$.{OBSERVE_ONLY}"), 0) == 0
+_PROFILED = not_(json_flag(CatalogProfileTask.summary, OBSERVE_ONLY))
 
 
 def _observe_only(checks: list[Any] | None) -> bool:
diff --git a/backend/app/data/recipe_imports.py b/backend/app/data/recipe_imports.py
index ee8d338c..e3d4598e 100644
--- a/backend/app/data/recipe_imports.py
+++ b/backend/app/data/recipe_imports.py
@@ -90,6 +90,7 @@ from app.data.recipe_types import (
 from app.data.xlsx_scan import WorkbookScan
 from app.db.base import new_id, utcnow
 from app.db.models import DataSource, ImportStaging, SourceSnapshot, TableBuild, TableImport, TableRecipe
+from app.db.portable import unique_violation
 
 logger = logging.getLogger(__name__)
 
@@ -2747,7 +2748,7 @@ async def commit_staging(session: AsyncSession, staging: ImportStaging, *, trial
         raise _publish_refused(e) from e
     except IntegrityError as e:
         await _back_to_drafting(session, staging_id)
-        if "data_sources.name" in str(e.orig if e.orig is not None else e):
+        if unique_violation(e, "data_sources", "name"):
             raise ImportRefused(409, "name_taken", f"名称「{name}」已被占用，请放弃这次导入后换一个名称") from e
         raise ImportRefused(500, "publish_failed", "导入失败：写入版本记录时出错，当前版本未受影响") from e
     except BaseException:
diff --git a/backend/app/data/source_changes.py b/backend/app/data/source_changes.py
index 5b625baf..51856bf0 100644
--- a/backend/app/data/source_changes.py
+++ b/backend/app/data/source_changes.py
@@ -37,6 +37,7 @@ from app.data import schema_diff as sd
 from app.data.names import name_key
 from app.db.base import utcnow
 from app.db.models_sources import SourceChange
+from app.db.portable import json_eq
 
 logger = logging.getLogger(__name__)
 
@@ -337,7 +338,7 @@ async def notify_after_job(source_id: str, job_id: str) -> int:
             n = int((await session.execute(select(func.count()).select_from(SourceChange).where(
                 SourceChange.source_id == source_id, SourceChange.severity == "action",
                 SourceChange.status == "open",
-                func.json_extract(SourceChange.detected_by, "$.job_id") == job_id))).scalar() or 0)
+                json_eq(SourceChange.detected_by, "job_id", job_id)))).scalar() or 0)
         if n:
             from app.notify import service
 
diff --git a/backend/app/data/table_versions.py b/backend/app/data/table_versions.py
index ccf212cf..39230169 100644
--- a/backend/app/data/table_versions.py
+++ b/backend/app/data/table_versions.py
@@ -540,10 +540,13 @@ _DB_SIDE_FILES = ("", "-wal", "-shm", "-journal")
 
 
 def _app_db_files() -> list[Path]:
-    """应用自己的库：元数据库、运行检查点库，以及实际连着的元数据库（测试里和 data_dir 下的不是同一个）。"""
+    """应用自己的库：元数据库、运行检查点库，以及实际连着的元数据库（测试里和 data_dir 下的不是同一个）。
+
+    应用库是 PostgreSQL 时，数据目录里的 agentlab.db、checkpoints.db 照样算：导入 PostgreSQL 之前的那份还留在那里，
+    里面是同一批元数据。连着的库这时是库名不是文件，不算进来。"""
     dbs = [settings.db_path, settings.checkpoint_path]
     try:
-        live = db_base.engine.url.database
+        live = db_base.engine.url.database if db_base.engine.dialect.name == "sqlite" else None
     except Exception:  # noqa: BLE001 - 取不到就只按配置里的路径判断
         live = None
     if live and live != ":memory:":
diff --git a/backend/app/db/base.py b/backend/app/db/base.py
index 24a40182..7e741218 100644
--- a/backend/app/db/base.py
+++ b/backend/app/db/base.py
@@ -1,16 +1,23 @@
 from __future__ import annotations
 
+import json
+import logging
+import math
+import re
 import uuid
 from datetime import datetime, timezone
 from typing import Any, AsyncIterator
 
-from sqlalchemy import JSON, DateTime, MetaData, event
-from sqlalchemy.ext.asyncio import AsyncSession, async_sessionmaker, create_async_engine
+from sqlalchemy import JSON, BigInteger, Column, DateTime, Integer, MetaData, event
+from sqlalchemy.ext.asyncio import AsyncEngine, AsyncSession, async_sessionmaker, create_async_engine
 from sqlalchemy.orm import DeclarativeBase, Mapped, mapped_column
+from sqlalchemy.pool import NullPool
 from sqlalchemy.types import TypeDecorator
 
 from app.core.config import settings
 
+logger = logging.getLogger(__name__)
+
 NAMING_CONVENTION = {
     "ix": "ix_%(column_0_label)s",
     "uq": "uq_%(table_name)s_%(column_0_name)s",
@@ -57,11 +64,31 @@ class UTCDateTime(TypeDecorator):
         return value.astimezone(timezone.utc)
 
 
+#: 应用库的 JSON 列：两种库上都是存原文的 JSON（PostgreSQL 的 json，不是 JSONB）。JSONB 会把对象里的键重新排序：
+#: 应用里不少地方按存进去的键的先后出东西（快照的列、表的先后、复核结论各段的先后），换成 JSONB 读回来就变了样，
+#: 测试当场抓到好几处。json 的代价是没有相等运算符：== 比较、DISTINCT、GROUP BY、ORDER BY 不能直接作用在整列上
+#: （应用里没有这种写法，test_db_portable 守着）；按里面某个键筛选走 db/portable 的 json_eq 等，只把取出来的那一小段
+#: 转成 JSONB 比较
+PortableJSON = JSON()
+
+
 class Base(DeclarativeBase):
     metadata = MetaData(naming_convention=NAMING_CONVENTION)
 
-    # 图定义、节点配置、事件负载都是任意形状的 JSON，统一映射到 SQLite 的 JSON 列
-    type_annotation_map = {dict[str, Any]: JSON, list[Any]: JSON, datetime: UTCDateTime}
+    # 图定义、节点配置、事件负载都是任意形状的 JSON，统一映射到 JSON 列（见 PortableJSON）
+    type_annotation_map = {dict[str, Any]: PortableJSON, list[Any]: PortableJSON, datetime: UTCDateTime}
+
+
+@event.listens_for(Column, "after_parent_attach")
+def _portable_integer(column: Column, table: Any) -> None:
+    """应用库的 Integer 列在 PostgreSQL 上换成 BIGINT（SQLite 照旧是 INTEGER，主键照旧是 rowid）。
+
+    SQLite 的 INTEGER 是 64 位，PostgreSQL 的只有 32 位：行数估计、字节数、累计的计数都可能过 21 亿。在列挂到表上
+    的那一刻换（定义模型时，任何查询之前）：建表是 BIGINT（自增主键是 BIGSERIAL），和这一列比较、写进这一列的绑定
+    参数也按 BIGINT 转换。只管挂在应用 metadata 上、类型正好是 Integer 的列；业务数据源那边的表不受影响。"""
+    if getattr(table, "metadata", None) is Base.metadata and type(column.type) is Integer \
+            and not column.type._variant_mapping:
+        column.type = Integer().with_variant(BigInteger(), "postgresql")
 
 
 class TimestampMixin:
@@ -101,16 +128,10 @@ def _stop_aiosqlite_once() -> None:
     aiosqlite.Connection.stop = stop  # type: ignore[method-assign]
 
 
+# 应用库是 PostgreSQL 时也照样打：上传表格、手工登记的 SQLite 业务库（data/engine）还是走 aiosqlite 的连接池
 _stop_aiosqlite_once()
-# pool_pre_ping：取连接前先探一下活。取消异常打进 SQLAlchemy 的清理流程时
-# （_close_connection 记完日志会把 CancelledError 原样抛出，跳过了把连接记录
-# 清空的那一行），已经关掉的连接会留在池里，下一个取到它的人拿到的是
-# "no active connection"。探活失败会被当成断开，换一条新的——SQLite 本地一次
-# SELECT 1 的代价，换池子不被污染。
-engine = create_async_engine(settings.db_url, echo=False, future=True, pool_pre_ping=True)
 
 
-@event.listens_for(engine.sync_engine, "connect")
 def _set_sqlite_pragma(dbapi_conn, _record):  # pragma: no cover - 驱动回调
     """WAL + 外键约束。WAL 让读写不互相阻塞，事件写入和前端轮询能并行。"""
     cur = dbapi_conn.cursor()
@@ -120,6 +141,92 @@ def _set_sqlite_pragma(dbapi_conn, _record):  # pragma: no cover - 驱动回调
     cur.close()
 
 
+def _finite(value: Any) -> Any:
+    if isinstance(value, float):
+        return value if math.isfinite(value) else None
+    if isinstance(value, dict):
+        return {k: _finite(v) for k, v in value.items()}
+    if isinstance(value, (list, tuple)):
+        return [_finite(v) for v in value]
+    return value
+
+
+def _no_nul(value: Any) -> Any:
+    if isinstance(value, str):
+        return value.replace("\x00", "")
+    if isinstance(value, dict):
+        return {_no_nul(k): _no_nul(v) for k, v in value.items()}
+    if isinstance(value, list):
+        return [_no_nul(v) for v in value]
+    return value
+
+
+def pg_json_dumps(value: Any) -> str:
+    """PostgreSQL 上写 JSON 列。它不收 NaN / Infinity（SQLite 照存）；字符串里的 \\u0000 json 列收，但一转成 JSONB
+    （按键筛选时，db/portable）、一取成文本就报错，那一整条查询跟着失败。
+
+    非有限的浮点写成 null（同浏览器的 JSON.stringify），字符串里的 NUL 字符去掉；平常的值一次 dumps 就过，
+    只有碰上了才多走一遍。"""
+    try:
+        text = json.dumps(value, allow_nan=False)
+    except ValueError:
+        text = json.dumps(_finite(value), allow_nan=False)
+    if "\\u0000" in text:
+        text = json.dumps(_no_nul(json.loads(text)), allow_nan=False)
+    return text
+
+
+#: 应用连 PostgreSQL 时报的 application_name。copy-to-postgres 按它认目标库上还有没有服务连着（它自己报的是 agentlab-copy）
+APPLICATION_NAME = "agentlab"
+
+
+def make_engine(url: str | None = None, *, application_name: str = APPLICATION_NAME) -> AsyncEngine:
+    """应用库的引擎。SQLite：WAL、外键、忙等，单个文件；PostgreSQL：连接池、方言调整（db/postgres.py）。
+
+    copy-to-postgres 建目标库的引擎也走这里，两边的列类型、排序规则是同一套。
+    """
+    url = url or settings.db_url
+    if url.startswith("sqlite"):
+        # pool_pre_ping：取连接前先探一下活。取消异常打进 SQLAlchemy 的清理流程时
+        # （_close_connection 记完日志会把 CancelledError 原样抛出，跳过了把连接记录
+        # 清空的那一行），已经关掉的连接会留在池里，下一个取到它的人拿到的是
+        # "no active connection"。探活失败会被当成断开，换一条新的——SQLite 本地一次
+        # SELECT 1 的代价，换池子不被污染。
+        made = create_async_engine(url, echo=False, future=True, pool_pre_ping=True)
+        event.listen(made.sync_engine, "connect", _set_sqlite_pragma)
+        return made
+    from app.db import postgres
+
+    pool: dict[str, Any] = (
+        {"poolclass": NullPool} if settings.db_pool_size <= 0 else {
+            "pool_size": settings.db_pool_size, "max_overflow": max(settings.db_max_overflow, 0),
+            "pool_timeout": settings.db_pool_timeout, "pool_recycle": settings.db_pool_recycle})
+    made = create_async_engine(
+        url, echo=False, future=True, pool_pre_ping=True, json_serializer=pg_json_dumps,
+        # 会话时区定成 UTC：时间列是不带时区的 UTC（UTCDateTime），库里 now() 之类的也按 UTC 算
+        connect_args={"server_settings": {"application_name": application_name, "timezone": "UTC"}},
+        **pool)
+    postgres.install(made.sync_engine.dialect)
+    return made
+
+
+def describe_database() -> str:
+    """启动日志里的一句：用的是哪种库、在哪（不写密码）。"""
+    from app.db.urls import describe
+
+    if settings.checkpoint_url:
+        points = f"断点在 PostgreSQL {describe(settings.checkpoint_url)}"
+    elif settings.db_dialect == "sqlite":
+        points = f"断点 {settings.checkpoint_path}"
+    else:
+        points = "断点在同一个库"
+    if settings.db_dialect == "sqlite":
+        return f"SQLite（{settings.db_path}，{points}）"
+    return f"PostgreSQL（{describe(settings.db_url)}，{points}）"
+
+
+engine = make_engine()
+
 SessionLocal = async_sessionmaker(engine, expire_on_commit=False, class_=AsyncSession)
 
 
@@ -129,8 +236,10 @@ async def get_session() -> AsyncIterator[AsyncSession]:
         yield session
 
 
-# 轻量迁移：create_all 只建新表，不给已有表加列。SQLite 的 ADD COLUMN
-# 便宜且带默认值回填，够用；等真需要改列类型再考虑 alembic。
+# 轻量迁移：create_all 只建新表，不给已有表加列。ADD COLUMN 便宜且带默认值回填，够用；等真需要改列类型再考虑 alembic。
+# 第三项照 SQLite 写（类型和缺省值的字面量）。PostgreSQL 上类型取模型里这一列的（按应用库的方言调整编译：String(n)
+# 是 VARCHAR、Integer 是 BIGINT、JSON 是 json、时间是 TIMESTAMP），缺省值取这里写的，布尔的 0 / 1 换成 false / true
+# （_column_ddl）。所以这里加的每一列模型里都得有：test_db_portable 守着
 _COLUMN_MIGRATIONS: list[tuple[str, str, str]] = [
     ("runs", "run_class", "TEXT DEFAULT 'exploratory'"),
     ("runs", "version", "INTEGER"),
@@ -274,44 +383,92 @@ _INDEX_MIGRATIONS: list[tuple[str, str, str | tuple[str, ...]]] = [
 
 #: 迁移补建的唯一索引：(索引名, 表, 列, 部分索引的条件, 建之前的去重语句)。只在索引还不存在时先去重再建——存量库里可能
 #: 已经有并发留下的重复行，直接建会失败。去重的规矩写在各自的语句里：多出的钩子行删掉（只留最早的那一行，它的密钥照旧
-#: 能用），多出的助手对话归档（不删，历史还在）
+#: 能用），多出的助手对话归档（不删，历史还在）。条件和语句里的 {false} / {true} 按方言换成布尔的字面量（SQLite 是 0 / 1）
 _UNIQUE_INDEX_MIGRATIONS: list[tuple[str, str, tuple[str, ...], str | None, str]] = [
     ("ux_app_hooks_app_name", "app_hooks", ("app_id", "name"), None,
      "DELETE FROM app_hooks WHERE id NOT IN (SELECT id FROM (SELECT id, ROW_NUMBER() OVER "
-     "(PARTITION BY app_id, name ORDER BY created_at, id) AS rn FROM app_hooks) WHERE rn = 1)"),
-    ("ux_conversations_app_owner", "conversations", ("app_id", "created_by"), "kind = 'app' AND archived = 0",
-     "UPDATE conversations SET archived = 1 WHERE kind = 'app' AND archived = 0 AND created_by IS NOT NULL "
+     "(PARTITION BY app_id, name ORDER BY created_at, id) AS rn FROM app_hooks) AS ranked WHERE rn = 1)"),
+    ("ux_conversations_app_owner", "conversations", ("app_id", "created_by"), "kind = 'app' AND archived = {false}",
+     "UPDATE conversations SET archived = {true} WHERE kind = 'app' AND archived = {false} AND created_by IS NOT NULL "
      "AND id NOT IN (SELECT id FROM (SELECT id, ROW_NUMBER() OVER (PARTITION BY app_id, created_by "
-     "ORDER BY last_active_at DESC, id) AS rn FROM conversations WHERE kind = 'app' AND archived = 0 "
-     "AND created_by IS NOT NULL) WHERE rn = 1)"),
+     "ORDER BY last_active_at DESC, id) AS rn FROM conversations WHERE kind = 'app' AND archived = {false} "
+     "AND created_by IS NOT NULL) AS ranked WHERE rn = 1)"),
 ]
 
+#: 布尔字面量：SQLite 的布尔列存 0 / 1
+_BOOL_LITERALS = {"sqlite": {"false": "0", "true": "1"}, "postgresql": {"false": "false", "true": "true"}}
+
+_DEFAULT = re.compile(r"\s+DEFAULT\s+(.+)$", re.I | re.S)
+
+
+def _column_ddl(dialect: Any, table: str, column: str, ddl: str) -> str:
+    """ADD COLUMN 里列名后面那一段。SQLite 原样用迁移表里写的；PostgreSQL 类型取模型里这一列的，缺省值取迁移表里的。"""
+    if dialect.name == "sqlite":
+        return ddl
+    from sqlalchemy import Boolean
+
+    from app.db.postgres import AppTypeCompiler
+
+    col = Base.metadata.tables[table].c[column]
+    out = AppTypeCompiler(dialect).process(col.type, type_expression=col)
+    if match := _DEFAULT.search(ddl):
+        default = match.group(1).strip()
+        if isinstance(col.type, Boolean):
+            default = {"0": "false", "1": "true"}.get(default, default)
+        out += f" DEFAULT {default}"
+    return out
+
 
 def _migrate(conn) -> None:  # pragma: no cover - 同步回调
-    from sqlalchemy import text
+    """给老库补列、补索引。已有的列和索引按 inspector 认（两种库同一套），再跑一遍什么都不做。"""
+    from sqlalchemy import inspect, text
 
+    dialect = conn.dialect
+    literals = _BOOL_LITERALS.get(dialect.name, _BOOL_LITERALS["postgresql"])
+    inspector = inspect(conn)
+    tables = set(inspector.get_table_names())
+    columns = {t: {c["name"] for c in inspector.get_columns(t)} for t in tables}
+    # IF NOT EXISTS：PostgreSQL 上多个进程同时启动，各自的检查和补列之间别人可能已经补上了（init_db 另外拿着锁）
+    add = "ADD COLUMN IF NOT EXISTS" if dialect.name == "postgresql" else "ADD COLUMN"
     for table, column, ddl in _COLUMN_MIGRATIONS:
-        cols = {row[1] for row in conn.execute(text(f"PRAGMA table_info({table})"))}
+        cols = columns.get(table)
         if cols and column not in cols:
-            conn.execute(text(f"ALTER TABLE {table} ADD COLUMN {column} {ddl}"))
-    for name, table, columns in _INDEX_MIGRATIONS:
-        wanted = (columns,) if isinstance(columns, str) else columns
-        cols = {row[1] for row in conn.execute(text(f"PRAGMA table_info({table})"))}
+            conn.execute(text(f"ALTER TABLE {table} {add} {column} {_column_ddl(dialect, table, column, ddl)}"))
+            cols.add(column)
+    for name, table, wanted in _INDEX_MIGRATIONS:
+        wanted = (wanted,) if isinstance(wanted, str) else wanted
+        cols = columns.get(table) or set()
         if all(c in cols for c in wanted):
             conn.execute(text(f"CREATE INDEX IF NOT EXISTS {name} ON {table} ({', '.join(wanted)})"))
-    for name, table, columns, where, dedupe in _UNIQUE_INDEX_MIGRATIONS:
-        cols = {row[1] for row in conn.execute(text(f"PRAGMA table_info({table})"))}
-        exists = conn.execute(text("SELECT 1 FROM sqlite_master WHERE type = 'index' AND name = :n"), {"n": name}).first()
-        if exists or not all(c in cols for c in columns):
+    for name, table, wanted, where, dedupe in _UNIQUE_INDEX_MIGRATIONS:
+        cols = columns.get(table) or set()
+        if not all(c in cols for c in wanted):
             continue
-        conn.execute(text(dedupe))
-        conn.execute(text(f"CREATE UNIQUE INDEX {name} ON {table} ({', '.join(columns)})"
-                          + (f" WHERE {where}" if where else "")))
+        if any(ix["name"] == name for ix in inspect(conn).get_indexes(table)):
+            continue
+        conn.execute(text(dedupe.format(**literals)))
+        conn.execute(text(f"CREATE UNIQUE INDEX {name} ON {table} ({', '.join(wanted)})"
+                          + (f" WHERE {where.format(**literals)}" if where else "")))
+
+
+#: init_db 在 PostgreSQL 上拿的会话级咨询锁的号：几个进程同时启动时，建表和迁移一个一个来（同一个号别处别用）
+_INIT_LOCK = 0x4167656E744C6162  # "AgentLab"
+
+
+async def create_schema(target: AsyncEngine) -> None:
+    """建表、补列补索引（create_all 只建新表，老库的新列靠 _migrate）。两种库同一套；copy-to-postgres 建目标库也用它。"""
+    from app.db import models  # noqa: F401  确保模型已注册到 metadata
+
+    async with target.begin() as conn:
+        if conn.dialect.name == "postgresql":
+            # 事务结束自动放锁。CREATE TABLE IF NOT EXISTS 在 PostgreSQL 上并发执行也会撞（系统表的唯一约束）
+            from sqlalchemy import text
+
+            await conn.execute(text("SELECT pg_advisory_xact_lock(:k)"), {"k": _INIT_LOCK})
+        await conn.run_sync(Base.metadata.create_all)
+        await conn.run_sync(_migrate)
 
 
 async def init_db() -> None:
-    from app.db import models  # noqa: F401  确保模型已注册到 metadata
-
-    async with engine.begin() as conn:
-        await conn.run_sync(Base.metadata.create_all)
-        await conn.run_sync(_migrate)
+    logger.info("应用库：%s", describe_database())
+    await create_schema(engine)
diff --git a/backend/app/db/models.py b/backend/app/db/models.py
index 860819a1..f10efdea 100644
--- a/backend/app/db/models.py
+++ b/backend/app/db/models.py
@@ -362,7 +362,8 @@ class CatalogDraftJob(Base, TimestampMixin):
     __table_args__ = (
         Index("ix_catalog_draft_jobs_source_created", "source_id", "created_at"),
         Index("ux_catalog_draft_jobs_active", "source_id", unique=True,
-              sqlite_where=text("status IN ('queued', 'running')")),
+              sqlite_where=text("status IN ('queued', 'running')"),
+              postgresql_where=text("status IN ('queued', 'running')")),
     )
 
     id: Mapped[str] = mapped_column(String(32), primary_key=True, default=new_id)
@@ -450,7 +451,8 @@ class CatalogProfileJob(Base, TimestampMixin):
     __table_args__ = (
         Index("ix_catalog_profile_jobs_source_created", "source_id", "created_at"),
         Index("ux_catalog_profile_jobs_active", "source_id", unique=True,
-              sqlite_where=text("status IN ('queued', 'running')")),
+              sqlite_where=text("status IN ('queued', 'running')"),
+              postgresql_where=text("status IN ('queued', 'running')")),
     )
 
     id: Mapped[str] = mapped_column(String(32), primary_key=True, default=new_id)
@@ -904,7 +906,8 @@ class Conversation(Base, TimestampMixin):
     # 一个人在一个应用里只有一段（未归档的）助手对话（D-e）。存量库由 db/base.py 的 _UNIQUE_INDEX_MIGRATIONS 补建。
     # created_by 为空（关登录又没填署名）的不受约束：SQLite 的唯一索引里 NULL 互不相等，那种情况靠接口里的进程内锁
     __table_args__ = (Index("ux_conversations_app_owner", "app_id", "created_by", unique=True,
-                            sqlite_where=text("kind = 'app' AND archived = 0")),)
+                            sqlite_where=text("kind = 'app' AND archived = 0"),
+                            postgresql_where=text("kind = 'app' AND archived = false")),)
 
     id: Mapped[str] = mapped_column(String(32), primary_key=True, default=new_id)
     title: Mapped[str] = mapped_column(String(200), default="")
diff --git a/backend/app/db/models_sources.py b/backend/app/db/models_sources.py
index 5495855e..2423fa50 100644
--- a/backend/app/db/models_sources.py
+++ b/backend/app/db/models_sources.py
@@ -19,10 +19,10 @@ from __future__ import annotations
 from datetime import datetime
 from typing import Any
 
-from sqlalchemy import JSON, Boolean, ForeignKey, Index, Integer, String, Text, UniqueConstraint, text
+from sqlalchemy import Boolean, ForeignKey, Index, Integer, String, Text, UniqueConstraint, text
 from sqlalchemy.orm import Mapped, mapped_column
 
-from app.db.base import Base, UTCDateTime, new_id, utcnow
+from app.db.base import Base, PortableJSON, UTCDateTime, new_id, utcnow
 
 
 class SourceObject(Base):
@@ -92,7 +92,8 @@ class IntrospectJob(Base):
     __table_args__ = (
         Index("ix_introspect_jobs_source_created", "source_id", "created_at"),
         Index("ux_introspect_jobs_active", "source_id", unique=True,
-              sqlite_where=text("status IN ('queued', 'running')")),
+              sqlite_where=text("status IN ('queued', 'running')"),
+              postgresql_where=text("status IN ('queued', 'running')")),
     )
 
     id: Mapped[str] = mapped_column(String(32), primary_key=True, default=new_id)
@@ -219,8 +220,8 @@ class SourceChange(Base):
     seen_count: Mapped[int] = mapped_column(Integer, default=1)
     detected_by: Mapped[dict[str, Any]] = mapped_column(default=dict)
     basis: Mapped[dict[str, Any] | None] = mapped_column(default=None)
-    before: Mapped[Any] = mapped_column(JSON, nullable=True, default=None)
-    after: Mapped[Any] = mapped_column(JSON, nullable=True, default=None)
+    before: Mapped[Any] = mapped_column(PortableJSON, nullable=True, default=None)
+    after: Mapped[Any] = mapped_column(PortableJSON, nullable=True, default=None)
     affects: Mapped[dict[str, Any] | None] = mapped_column(default=None)
     struct_version_before: Mapped[int | None] = mapped_column(Integer, default=None)
     struct_version_after: Mapped[int | None] = mapped_column(Integer, default=None)
diff --git a/backend/app/db/portable.py b/backend/app/db/portable.py
new file mode 100644
index 00000000..4d643d1d
--- /dev/null
+++ b/backend/app/db/portable.py
@@ -0,0 +1,235 @@
+"""应用库上 SQLite、PostgreSQL 写法不一样的那几样，收成按方言编译的表达式。
+
+只给应用库（agentlab.db / AGENTLAB_DATABASE_URL）用；发给业务数据源的 SQL 不走这里。
+
+**按 JSON 列里的键筛选。** SQLite 用 json_extract：取出来是 SQL 标量（字符串是文本、数字是数字、true 是 1、
+没有这个键或值为 null 是 NULL），和 Python 值比是带类型的比较（数字 3 不等于字符串 "3"）。PostgreSQL 的 JSON 列是
+存原文的 json（db/base.PortableJSON），用 -> / ->> 取，要比较的只把取出来的那一小段转成 JSONB：
+
+- json_eq：PostgreSQL 上按 JSONB 相等比（`(col -> 'k')::jsonb = '3'::jsonb`），同样带类型，和 SQLite 一致；
+- json_text：只要文本（字符串原样、数字是它的写法），PostgreSQL 上是 ->>；
+- json_flag：标记位「真」（true、非零的数）：没有这个键、null、false、0 都算假；
+- json_is_string：这个键的值是不是字符串（SQLite 的 json_type 叫 text，PostgreSQL 的 jsonb_typeof 叫 string）。
+
+键名只收标识符（字母、数字、下划线），直接写进 SQL：键都是代码里的常量，写进去语句缓存也按它区分。
+
+**插入，撞了唯一键就什么都不做。** insert_ignore 按会话连着的库挑 sqlite / postgresql 的 insert，两边的
+on_conflict_do_nothing 是同一个接口。
+
+**撞的是哪个唯一约束。** unique_violation 认 IntegrityError：SQLite 的报错是「UNIQUE constraint failed: 表.列」，
+PostgreSQL（asyncpg）的是 23505，表名、DETAIL 里的「Key (列)=」分别带着。不靠约束名（命名规则改了也认得出）。
+"""
+
+from __future__ import annotations
+
+import json
+import re
+from typing import Any
+
+from sqlalchemy import Boolean, String, bindparam, literal_column
+from sqlalchemy.ext.compiler import compiles
+from sqlalchemy.sql.functions import FunctionElement
+from sqlalchemy.types import TypeDecorator
+
+_KEY = re.compile(r"[A-Za-z_][A-Za-z0-9_]*\Z")
+
+
+def _key(name: str) -> Any:
+    if not _KEY.match(name):
+        raise ValueError(f"JSON 键名只能是标识符：{name!r}")
+    return literal_column(name)
+
+
+class _JsonScalar(TypeDecorator):
+    """json_eq 右边的值：SQLite 原样绑定（和 json_extract 取出的标量比），PostgreSQL 绑定成 JSON 文本再转 JSONB。"""
+
+    impl = String
+    cache_ok = True
+
+    def process_bind_param(self, value: Any, dialect: Any) -> Any:
+        if dialect.name == "postgresql":
+            return json.dumps(value, ensure_ascii=False)
+        return value
+
+
+class json_text(FunctionElement[str]):
+    """JSON 列顶层键的值，当文本用。"""
+
+    type = String()
+    inherit_cache = True
+    name = "json_text"
+
+    def __init__(self, column: Any, key: str) -> None:
+        super().__init__(column, _key(key))
+
+
+class _JsonEq(FunctionElement[bool]):
+    type = Boolean()
+    inherit_cache = True
+    name = "json_eq"
+
+    def __init__(self, column: Any, key: str, value: Any) -> None:
+        super().__init__(column, _key(key), bindparam(None, value, type_=_JsonScalar()))
+
+
+class _JsonNull(FunctionElement[bool]):
+    type = Boolean()
+    inherit_cache = True
+    name = "json_null"
+
+    def __init__(self, column: Any, key: str) -> None:
+        super().__init__(column, _key(key))
+
+
+def json_eq(column: Any, key: str, value: Any) -> Any:
+    """JSON 列顶层键的值等于 value（带类型的比较，见模块说明）。value 为 None 时是「没有这个键或值为 null」。
+
+    None 用另一个表达式：语句缓存不按绑定参数的值区分，同一个表达式不能因为值是 None 编译成两样。"""
+    return _JsonNull(column, key) if value is None else _JsonEq(column, key, value)
+
+
+class json_flag(FunctionElement[bool]):
+    """JSON 列顶层键是「真」的标记位：true 或非零的数（字符串也算真，同 SQLite）。没有这个键、null、false、0 是假。"""
+
+    type = Boolean()
+    inherit_cache = True
+    name = "json_flag"
+
+    def __init__(self, column: Any, key: str) -> None:
+        super().__init__(column, _key(key))
+
+
+class json_is_string(FunctionElement[bool]):
+    """JSON 列顶层键的值是字符串。"""
+
+    type = Boolean()
+    inherit_cache = True
+    name = "json_is_string"
+
+    def __init__(self, column: Any, key: str) -> None:
+        super().__init__(column, _key(key))
+
+
+def _parts(element: Any, compiler: Any, **kw: Any) -> tuple[str, str, list[Any]]:
+    column, key, *rest = list(element.clauses)
+    return compiler.process(column, **kw), key.name, rest
+
+
+# ---- SQLite（缺省）----
+
+
+@compiles(json_text)
+def _json_text_sqlite(element: Any, compiler: Any, **kw: Any) -> str:
+    col, key, _ = _parts(element, compiler, **kw)
+    return f"json_extract({col}, '$.{key}')"
+
+
+@compiles(_JsonEq)
+def _json_eq_sqlite(element: Any, compiler: Any, **kw: Any) -> str:
+    col, key, (value,) = _parts(element, compiler, **kw)
+    return f"(json_extract({col}, '$.{key}') = {compiler.process(value, **kw)})"
+
+
+@compiles(_JsonNull)
+def _json_null_sqlite(element: Any, compiler: Any, **kw: Any) -> str:
+    col, key, _ = _parts(element, compiler, **kw)
+    return f"(json_extract({col}, '$.{key}') IS NULL)"
+
+
+@compiles(json_flag)
+def _json_flag_sqlite(element: Any, compiler: Any, **kw: Any) -> str:
+    col, key, _ = _parts(element, compiler, **kw)
+    return f"(coalesce(json_extract({col}, '$.{key}'), 0) != 0)"
+
+
+@compiles(json_is_string)
+def _json_is_string_sqlite(element: Any, compiler: Any, **kw: Any) -> str:
+    col, key, _ = _parts(element, compiler, **kw)
+    return f"(json_type({col}, '$.{key}') = 'text')"
+
+
+# ---- PostgreSQL（应用库的 JSON 列是 json）----
+
+
+def _got(col: str, key: str) -> str:
+    """取出的那一段转成 JSONB：json 没有相等运算符。列本身是 JSONB 也照样成立。"""
+    return f"CAST(({col} -> '{key}') AS JSONB)"
+
+
+@compiles(json_text, "postgresql")
+def _json_text_pg(element: Any, compiler: Any, **kw: Any) -> str:
+    col, key, _ = _parts(element, compiler, **kw)
+    return f"({col} ->> '{key}')"
+
+
+@compiles(_JsonEq, "postgresql")
+def _json_eq_pg(element: Any, compiler: Any, **kw: Any) -> str:
+    col, key, (value,) = _parts(element, compiler, **kw)
+    return f"({_got(col, key)} = CAST({compiler.process(value, **kw)} AS JSONB))"
+
+
+@compiles(_JsonNull, "postgresql")
+def _json_null_pg(element: Any, compiler: Any, **kw: Any) -> str:
+    # json_extract 对「没有这个键」和「值为 null」都给 NULL；-> 对后者给的是 JSON 的 null
+    col, key, _ = _parts(element, compiler, **kw)
+    return f"(coalesce({_got(col, key)}, 'null'::jsonb) = 'null'::jsonb)"
+
+
+@compiles(json_flag, "postgresql")
+def _json_flag_pg(element: Any, compiler: Any, **kw: Any) -> str:
+    col, key, _ = _parts(element, compiler, **kw)
+    return f"(coalesce({_got(col, key)}, 'null'::jsonb) NOT IN ('null'::jsonb, 'false'::jsonb, '0'::jsonb))"
+
+
+@compiles(json_is_string, "postgresql")
+def _json_is_string_pg(element: Any, compiler: Any, **kw: Any) -> str:
+    col, key, _ = _parts(element, compiler, **kw)
+    return f"(jsonb_typeof({_got(col, key)}) = 'string')"
+
+
+# ---- 插入，撞了唯一键就跳过 ----
+
+
+def dialect_of(session: Any) -> str:
+    """会话（AsyncSession / Session）连着的库的方言名。"""
+    return session.get_bind().dialect.name
+
+
+def insert_ignore(session: Any, table: Any) -> Any:
+    """按会话连着的库挑方言的 insert，调用方接着 .values(...).on_conflict_do_nothing(index_elements=[...])。"""
+    if dialect_of(session) == "postgresql":
+        from sqlalchemy.dialects.postgresql import insert
+    else:
+        from sqlalchemy.dialects.sqlite import insert
+    return insert(table)
+
+
+# ---- 撞的是哪个唯一约束 ----
+
+_SQLITE_UNIQUE = "UNIQUE constraint failed:"
+_PG_KEY = re.compile(r"Key \(([^)]*)\)=")
+
+
+def _driver_error(error: BaseException) -> Any:
+    """SQLAlchemy 的异常 → asyncpg 自己的异常（在 orig 的 __cause__ 上；orig 只抄了 sqlstate，没有表名和 DETAIL）。"""
+    seen: Any = getattr(error, "orig", None) or error
+    for _ in range(4):
+        if getattr(seen, "sqlstate", None) and hasattr(seen, "table_name"):
+            return seen
+        seen = getattr(seen, "__cause__", None)
+        if seen is None:
+            break
+    return None
+
+
+def unique_violation(error: BaseException, table: str, *columns: str) -> bool:
+    """这个 IntegrityError 是不是撞了 table 上正好这几列的唯一约束（主键、唯一索引都算）。"""
+    text = str(getattr(error, "orig", None) or error)
+    if _SQLITE_UNIQUE in text:
+        failed = text.split(_SQLITE_UNIQUE, 1)[1].splitlines()[0]
+        return {part.strip() for part in failed.split(",")} == {f"{table}.{c}" for c in columns}
+    cause = _driver_error(error)
+    if cause is None or getattr(cause, "sqlstate", None) != "23505" or getattr(cause, "table_name", None) != table:
+        return False
+    match = _PG_KEY.search(getattr(cause, "detail", None) or "")
+    return bool(match) and [c.strip().strip('"') for c in match.group(1).split(",")] == list(columns)
diff --git a/backend/app/db/postgres.py b/backend/app/db/postgres.py
new file mode 100644
index 00000000..74318aa3
--- /dev/null
+++ b/backend/app/db/postgres.py
@@ -0,0 +1,76 @@
+"""应用库是 PostgreSQL 时，让它在 SQLite 上写成的那些假设下照样成立。
+
+只装在应用库那个引擎的方言实例上（db/base.make_engine），业务数据源的 PostgreSQL 引擎不受影响。
+
+**建表的列类型。** 应用是在 SQLite 上写成的：SQLite 不查 VARCHAR 的长度，INTEGER 是 64 位。PostgreSQL 上
+VARCHAR(n) 超长直接报错、INTEGER 只有 32 位。模型里的 String(n) 是写给人看的「大致多长」，从来没有被库约束过：
+逐列核对只核得到测试走到的值，漏一处就是线上的写入失败，从 SQLite 导过来的存量数据里也可能已经有超长的。所以
+应用库上 String(n) 建成不限长的 VARCHAR（PostgreSQL 里 varchar、varchar(n)、text 存储和性能一样，限长只多一次
+检查）。CAST(x AS VARCHAR(n)) 这种查询里的写法不动——那是截断的意思。Integer 列在 PostgreSQL 上是 BIGINT：
+那是在模型这一层换的（db/base._portable_integer），绑定参数的类型转换跟着列走，大数不在半路溢出。
+
+**ORDER BY 里 NULL 的位置。** SQLite 升序 NULL 在前、降序 NULL 在后，PostgreSQL 正好相反。应用里两百多处排序，
+可空的列（开始时间、到期时间、发布时间……）排出来的先后要和 SQLite 一致：可空列上没写 nulls_first / nulls_last
+的 ASC 补 NULLS FIRST、DESC 补 NULLS LAST，ORDER BY 里直接写列名（隐含 ASC）的同样补上。不可空的列不动——
+补了会让索引用不上，又没有 NULL 可排。窗口函数 OVER (ORDER BY …) 里同样补。原生 text() 里写的 ORDER BY 不经过
+这里，要自己写明（db/base 的去重语句里就写了）。
+"""
+
+from __future__ import annotations
+
+from typing import Any
+
+from sqlalchemy import Column
+from sqlalchemy.dialects.postgresql.asyncpg import PGCompiler_asyncpg
+from sqlalchemy.dialects.postgresql.base import PGTypeCompiler
+from sqlalchemy.sql import operators
+from sqlalchemy.sql.elements import ClauseList, UnaryExpression
+
+#: 外层已经写了 nulls_first / nulls_last：里面那一层 ASC / DESC 不再补
+_EXPLICIT = "_agentlab_explicit_nulls"
+
+
+def _nullable(element: Any) -> bool:
+    return isinstance(element, Column) and bool(element.nullable) and not element.primary_key
+
+
+class AppTypeCompiler(PGTypeCompiler):
+    def visit_string(self, type_: Any, **kw: Any) -> str:
+        if type_.length and isinstance(kw.get("type_expression"), Column):
+            return "VARCHAR"
+        return super().visit_string(type_, **kw)
+
+
+def _ordered(clauses: Any) -> list[Any]:
+    """ORDER BY 里直接写的可空列补成 ASC（visit_unary 再给它补 NULLS FIRST）。"""
+    return [c.asc() if _nullable(c) else c for c in clauses]
+
+
+class AppCompiler(PGCompiler_asyncpg):
+    def order_by_clause(self, select: Any, **kw: Any) -> str:
+        order_by = self._generate_delimited_list(_ordered(select._order_by_clauses), ", ", **kw)
+        return " ORDER BY " + order_by if order_by else ""
+
+    def visit_over(self, over: Any, **kw: Any) -> str:
+        clauses = list(over.order_by) if over.order_by is not None else []
+        if any(_nullable(c) for c in clauses):
+            # 在副本上换：语句对象可能被缓存、被别处共用，不能改原件
+            over = over._clone()
+            over.order_by = ClauseList(*_ordered(clauses))
+        return super().visit_over(over, **kw)
+
+    def visit_unary(self, unary: UnaryExpression, **kw: Any) -> str:
+        modifier = unary.modifier
+        if modifier in (operators.nulls_first_op, operators.nulls_last_op):
+            return super().visit_unary(unary, **{**kw, _EXPLICIT: True})
+        explicit = kw.pop(_EXPLICIT, False)
+        text = super().visit_unary(unary, **kw)
+        if not explicit and modifier in (operators.asc_op, operators.desc_op) and _nullable(unary.element):
+            text += " NULLS FIRST" if modifier is operators.asc_op else " NULLS LAST"
+        return text
+
+
+def install(dialect: Any) -> None:
+    """装到应用库引擎的方言实例上。"""
+    dialect.statement_compiler = AppCompiler
+    dialect.type_compiler_instance = dialect.type_compiler = AppTypeCompiler(dialect)
diff --git a/backend/app/db/urls.py b/backend/app/db/urls.py
new file mode 100644
index 00000000..c1b8855f
--- /dev/null
+++ b/backend/app/db/urls.py
@@ -0,0 +1,57 @@
+"""应用库、断点库的地址：规范写法、换算成 psycopg 用的连接串、写进日志的样子（不带密码）。
+
+不依赖 app.core.config：配置的校验器要调这里，这里再导 config 就成了循环导入。
+"""
+
+from __future__ import annotations
+
+from sqlalchemy.engine import URL, make_url
+from sqlalchemy.exc import ArgumentError
+
+#: 应用库认的写法。asyncpg 是 SQLAlchemy 这边的驱动；postgresql:// / postgres:// 是常见的通用写法，一律换成 asyncpg
+_APP_SCHEMES = {"postgresql+asyncpg", "postgresql", "postgres"}
+#: 断点库认的写法：psycopg 只认 libpq 的 postgresql:// / postgres://；带驱动名的 SQLAlchemy 写法也收，去掉驱动名
+_CHECKPOINT_SCHEMES = {"postgresql", "postgres", "postgresql+psycopg", "postgresql+asyncpg"}
+
+#: asyncpg 和 libpq 对 SSL 的参数名不一样：asyncpg 是 ssl=require，libpq 是 sslmode=require（取值同一套）
+_ASYNCPG_TO_LIBPQ = {"ssl": "sslmode"}
+
+
+def _parse(raw: str, schemes: set[str], example: str) -> URL:
+    try:
+        url = make_url(raw)
+    except ArgumentError:
+        raise ValueError(f"认不出这个地址，应当写成 {example}") from None
+    if url.drivername not in schemes:
+        raise ValueError(f"只认 PostgreSQL（{example}），不认 {url.drivername}://；用 SQLite 就不要设这一项")
+    if not url.database:
+        raise ValueError(f"地址里要写库名，例如 {example}")
+    return url
+
+
+def normalize_database_url(raw: str) -> str:
+    """AGENTLAB_DATABASE_URL → postgresql+asyncpg://…（密码原样保留）。认不出的写法抛 ValueError。"""
+    url = _parse(raw, _APP_SCHEMES, "postgresql+asyncpg://用户:密码@主机:5432/库名")
+    return url.set(drivername="postgresql+asyncpg").render_as_string(hide_password=False)
+
+
+def normalize_checkpoint_url(raw: str) -> str:
+    """AGENTLAB_CHECKPOINT_URL → libpq 认的 postgresql://…。认不出的写法抛 ValueError。"""
+    url = _parse(raw, _CHECKPOINT_SCHEMES, "postgresql://用户:密码@主机:5432/库名")
+    return libpq_conninfo(url.render_as_string(hide_password=False))
+
+
+def libpq_conninfo(database_url: str) -> str:
+    """SQLAlchemy 的地址 → psycopg 的连接串：去掉驱动名，asyncpg 写法的参数换成 libpq 的。"""
+    url = make_url(database_url)
+    query = {_ASYNCPG_TO_LIBPQ.get(k, k): v for k, v in url.query.items()}
+    return url.set(drivername="postgresql", query=query).render_as_string(hide_password=False)
+
+
+def describe(database_url: str) -> str:
+    """写进日志的样子：主机、端口、库名、用户，不写密码。"""
+    url = make_url(database_url)
+    host = url.host or "本机套接字"
+    port = f":{url.port}" if url.port else ""
+    user = f"，用户 {url.username}" if url.username else ""
+    return f"{host}{port}/{url.database}{user}"
diff --git a/backend/app/engine/checkpoints.py b/backend/app/engine/checkpoints.py
new file mode 100644
index 00000000..bd267ccf
--- /dev/null
+++ b/backend/app/engine/checkpoints.py
@@ -0,0 +1,87 @@
+"""LangGraph 的断点库：应用库是 SQLite 时用 AsyncSqliteSaver（数据目录里的 checkpoints.db，和业务表分开免得抢写锁），
+是 PostgreSQL 时用官方的 AsyncPostgresSaver（psycopg 3 + 连接池），放在同一个库里，AGENTLAB_CHECKPOINT_URL 另给就放那里。
+
+它建的四张表（checkpoints、checkpoint_blobs、checkpoint_writes、checkpoint_migrations）和应用的表不重名
+（test_db_portable 守着），所以同一个库、同一个 schema 就行。
+
+应用里读断点一律走 saver 的公开接口（aget_state / aget_state_history / aget_tuple / alist），不直接查这几张表：
+两种库的表结构完全不一样（SQLite 整份断点是一个 msgpack，PostgreSQL 拆成 JSONB 加 blob）。
+"""
+
+from __future__ import annotations
+
+import contextlib
+from collections.abc import AsyncIterator
+from pathlib import Path
+from typing import Any
+
+from langgraph.checkpoint.base import BaseCheckpointSaver
+
+from app.core.config import settings
+
+#: 建断点表时拿的会话级咨询锁的号：几个进程同时启动，各自的 setup（建表、记迁移版本）一个一个来
+_SETUP_LOCK = 0x4167656E74436B70  # "AgentCkp"
+
+
+def _pool_size() -> int:
+    # 运行里每个超步写一次断点、每个任务写一次 pending writes，都是一来一回的短操作。并发运行多时多给几条
+    return max(4, min(settings.max_concurrent_runs, 20))
+
+
+@contextlib.asynccontextmanager
+async def open_postgres_saver(conninfo: str, *, max_size: int | None = None,
+                              application_name: str = "agentlab") -> AsyncIterator[BaseCheckpointSaver]:
+    """PostgreSQL 的断点库：开连接池、建表（幂等），退出时关池子。application_name 同应用库（db/base.APPLICATION_NAME）。"""
+    from langgraph.checkpoint.postgres.aio import AsyncPostgresSaver
+    from psycopg.rows import dict_row
+    from psycopg_pool import AsyncConnectionPool
+
+    # 连接参数照 AsyncPostgresSaver.from_conn_string：自动提交（它不自己管事务）、语句第一次执行就预备、行按 dict 取
+    pool = AsyncConnectionPool(
+        conninfo, min_size=1, max_size=max_size or _pool_size(), open=False,
+        kwargs={"autocommit": True, "prepare_threshold": 0, "row_factory": dict_row,
+                "application_name": application_name},
+        check=AsyncConnectionPool.check_connection, name="agentlab-checkpoints")
+    await pool.open(wait=True)
+    try:
+        saver = AsyncPostgresSaver(pool)  # type: ignore[arg-type]
+        async with pool.connection() as conn:
+            await conn.execute("SELECT pg_advisory_lock(%s)", (_SETUP_LOCK,))
+            try:
+                await saver.setup()
+            finally:
+                await conn.execute("SELECT pg_advisory_unlock(%s)", (_SETUP_LOCK,))
+        yield saver
+    finally:
+        await pool.close()
+
+
+@contextlib.asynccontextmanager
+async def open_sqlite_saver(path: Path | str) -> AsyncIterator[BaseCheckpointSaver]:
+    from langgraph.checkpoint.sqlite.aio import AsyncSqliteSaver
+
+    async with AsyncSqliteSaver.from_conn_string(str(path)) as saver:
+        yield saver
+
+
+def open_saver() -> contextlib.AbstractAsyncContextManager[BaseCheckpointSaver]:
+    """按配置开这个进程的断点库。"""
+    conninfo = settings.checkpoint_conninfo
+    if conninfo:
+        return open_postgres_saver(conninfo)
+    return open_sqlite_saver(settings.checkpoint_path)
+
+
+def kind() -> str:
+    """"sqlite" 或 "postgresql"：断点库放在哪种库里。"""
+    return "postgresql" if settings.checkpoint_conninfo else "sqlite"
+
+
+async def count(saver: Any, thread_id: str | None = None) -> tuple[int, int]:
+    """(断点条数, pending writes 条数)。thread_id 为空数全部。copy-to-postgres 核对用，走公开接口。"""
+    config = {"configurable": {"thread_id": thread_id}} if thread_id else None
+    checkpoints = writes = 0
+    async for tup in saver.alist(config):
+        checkpoints += 1
+        writes += len(tup.pending_writes or ())
+    return checkpoints, writes
diff --git a/backend/app/engine/runner.py b/backend/app/engine/runner.py
index 1b3d020c..b33e472a 100644
--- a/backend/app/engine/runner.py
+++ b/backend/app/engine/runner.py
@@ -10,7 +10,7 @@ from collections.abc import Callable, Sequence
 from datetime import datetime, timezone
 from typing import Any
 
-from langgraph.checkpoint.sqlite.aio import AsyncSqliteSaver
+from langgraph.checkpoint.base import BaseCheckpointSaver
 from langgraph.errors import GraphRecursionError
 from langgraph.types import Command
 from sqlalchemy import case, func, select, update
@@ -71,7 +71,7 @@ class RunManager:
 
     def __init__(self) -> None:
         self._tasks: dict[str, asyncio.Task[None]] = {}
-        self._checkpointer: AsyncSqliteSaver | None = None
+        self._checkpointer: BaseCheckpointSaver | None = None
         self._cm: Any = None
         self._semaphore = asyncio.Semaphore(settings.max_concurrent_runs)
         #: 正在关停。此时收到的取消来自关停而不是用户，运行要记成可恢复的中断
@@ -86,7 +86,10 @@ class RunManager:
     async def setup(self) -> None:
         self._closing = False
         settings.ensure_dirs()
-        self._cm = AsyncSqliteSaver.from_conn_string(str(settings.checkpoint_path))
+        # SQLite：数据目录里的 checkpoints.db；PostgreSQL：同一个库（或 AGENTLAB_CHECKPOINT_URL），见 engine/checkpoints.py
+        from app.engine.checkpoints import open_saver
+
+        self._cm = open_saver()
         self._checkpointer = await self._cm.__aenter__()
         # 上次进程被强杀时留下的记录。running 和 queued 要分开处理：
         # running 至少跑过一步、有 checkpoint，可以续；queued 还在排队，
@@ -163,7 +166,7 @@ class RunManager:
                 await self._cm.__aexit__(None, None, None)
 
     @property
-    def checkpointer(self) -> AsyncSqliteSaver:
+    def checkpointer(self) -> BaseCheckpointSaver:
         if self._checkpointer is None:
             raise RuntimeError("RunManager 还没初始化")
         return self._checkpointer
@@ -889,6 +892,15 @@ class RunManager:
                 try:
                     await self._finalize(run_id, status, error, final_state, elapsed,
                                          terminal=terminal, error_node=error_node, end_reason=end_reason)
+                    # 记 action.unknown、安排核实也算收尾：做完才把自己摘掉。以前摘掉之后才做，等运行「不在跑了」
+                    # 再去读事件的一方（接口、测试）有一小段读不到这一条；库慢一点（PostgreSQL 满载时）就读不到
+                    if pending_action is not None:
+                        from app.process.actions import on_unknown
+
+                        try:
+                            await on_unknown(pending_action)
+                        except Exception:  # noqa: BLE001 - 运行已经收成挂起；没安排上的核实，下次启动时 actions.startup 补上
+                            logger.exception("run %s 的动作 %s 结果未知，安排核实时出错", run_id, pending_action)
                 finally:
                     # 收尾被打断（关停时的取消、库连接出错）也得把自己摘掉。以前写在
                     # _finalize 后面，一被打断就漏掉，留下的任务让下一次 shutdown 的
@@ -896,13 +908,6 @@ class RunManager:
                     self._finalizing.discard(run_id)
                     self._tasks.pop(run_id, None)
                     self._stopped_by.pop(run_id, None)
-                if pending_action is not None:
-                    from app.process.actions import on_unknown
-
-                    try:
-                        await on_unknown(pending_action)
-                    except Exception:  # noqa: BLE001 - 运行已经收成挂起；没安排上的核实，下次启动时 actions.startup 补上
-                        logger.exception("run %s 的动作 %s 结果未知，安排核实时出错", run_id, pending_action)
                 # 运行到终态就把沙箱会话收掉。thread_id 每个 run 都是新的，
                 # 不收的话每跑一次带代码节点的图就多一台常驻 microVM（几百 MB），
                 # 而且没有任何自动回收路径会碰它——闲置回收只在"下次有人执行
diff --git a/backend/app/files/store.py b/backend/app/files/store.py
index f3f74aa5..4b466005 100644
--- a/backend/app/files/store.py
+++ b/backend/app/files/store.py
@@ -294,7 +294,7 @@ def accept_problem(setting: dict[str, Any] | None, *, name: str, mime: str, size
 # --------------------------------------------------------------------------
 
 #: 还没绑到记录上：JSON 列显式写过 None 的存的是 JSON 的 null，不是 SQL 的 NULL，两种都算
-_NO_RECORD = text("(files.bound_record IS NULL OR files.bound_record = 'null')")
+_NO_RECORD = text("(files.bound_record IS NULL OR CAST(files.bound_record AS TEXT) = 'null')")
 
 
 def file_fields(form: Any) -> list[str]:
diff --git a/backend/app/ledger/issue.py b/backend/app/ledger/issue.py
index 66f701bd..0c451172 100644
--- a/backend/app/ledger/issue.py
+++ b/backend/app/ledger/issue.py
@@ -44,6 +44,7 @@ from sqlalchemy import func, select
 
 from app.db.base import SessionLocal
 from app.db.models import Run, Workflow
+from app.db.portable import json_eq
 
 logger = logging.getLogger(__name__)
 
@@ -150,9 +151,9 @@ async def issued_today(session: Any) -> int:
 
 async def issued_runs(session: Any, run_id: str) -> list[Run]:
     """这次运行按口径出具过的正式运行（origin.source_run 是它），新的在前。origin_kind 有索引，先按它筛再看 origin
-    （json_extract，同 auth/keys 认幂等键的写法）。"""
+    （db/portable.json_eq，同 auth/keys 认幂等键的写法）。"""
     rows = (await session.execute(select(Run).where(
-        Run.origin_kind == ORIGIN, func.json_extract(Run.origin, "$.source_run") == run_id)
+        Run.origin_kind == ORIGIN, json_eq(Run.origin, "source_run", run_id))
         .order_by(Run.created_at.desc()))).scalars()
     return list(rows)
 
diff --git a/backend/app/ledger/recall.py b/backend/app/ledger/recall.py
index 62bf2dbe..3227c66f 100644
--- a/backend/app/ledger/recall.py
+++ b/backend/app/ledger/recall.py
@@ -66,11 +66,12 @@ from dataclasses import dataclass, field
 from datetime import datetime, timedelta, timezone
 from typing import Any
 
-from sqlalchemy import func, select
+from sqlalchemy import func, not_, select
 
 from app.core.events import EventType
 from app.db.base import SessionLocal, utcnow
 from app.db.models import Run, RunEvent, Workflow
+from app.db.portable import json_eq, json_flag, json_text
 from app.ledger import uses as ledger_uses
 
 logger = logging.getLogger(__name__)
@@ -225,10 +226,9 @@ def source_cards(graph: Any) -> list[str]:
 async def recall_runs(session: Any, workflow_id: str, new_version: int | None = None) -> list[Run]:
     """以 W（新版本 N）发起过的召回运行（试算的不算），新的在前。origin_kind 有索引，先按它筛再看 origin。"""
     stmt = select(Run).where(Run.origin_kind == ORIGIN,
-                             func.json_extract(Run.origin, "$.workflow_id") == workflow_id,
-                             func.coalesce(func.json_extract(Run.origin, "$.probe"), 0) == 0)
+                             json_eq(Run.origin, "workflow_id", workflow_id), not_(json_flag(Run.origin, "probe")))
     if new_version is not None:
-        stmt = stmt.where(func.json_extract(Run.origin, "$.to_version") == int(new_version))
+        stmt = stmt.where(json_eq(Run.origin, "to_version", int(new_version)))
     return list((await session.execute(stmt.order_by(Run.created_at.desc()))).scalars())
 
 
@@ -567,9 +567,8 @@ async def version_recall_counts(session: Any, workflow_id: str, version: int) ->
         state, _ = await outcome_of(session, run)
         changed += state == "changed"
     as_old = int(await session.scalar(select(func.count()).select_from(Run).where(
-        Run.origin_kind == ORIGIN, func.json_extract(Run.origin, "$.workflow_id") == workflow_id,
-        func.json_extract(Run.origin, "$.from_version") == int(version),
-        func.coalesce(func.json_extract(Run.origin, "$.probe"), 0) == 0)) or 0)
+        Run.origin_kind == ORIGIN, json_eq(Run.origin, "workflow_id", workflow_id),
+        json_eq(Run.origin, "from_version", int(version)), not_(json_flag(Run.origin, "probe")))) or 0)
     return {"groups": len(as_new), "changed": changed, "recalled_from": as_old}
 
 
@@ -986,7 +985,7 @@ async def answer_marks(session: Any, run_id: str, principal: Any) -> dict[str, A
         select(Task, Run.origin).join(Run, Run.id == Task.run_id)
         .where(Task.kind == TASK_KIND, Task.status == "pending",
                (Task.run_id == run_id) | ((Run.origin_kind == ORIGIN)
-                                          & (func.instr(func.json_extract(Run.origin, "$.uses"), run_id) > 0)))
+                                          & json_text(Run.origin, "uses").contains(run_id, autoescape=True)))
         .order_by(Task.created_at, Task.id))).all()
     mine = await _assignments(session, [t.id for t, _ in candidates])
     tasks: list[dict[str, Any]] = []
@@ -1134,8 +1133,8 @@ async def _explore_snapshots(session: Any, source: Any, tables: Iterable[str], *
     stmt = (select(Artifact.id, Artifact.meta, Run.id, Run.finished_at).join(Run, Run.id == Artifact.run_id)
             .where(Artifact.kind == QUERY_SNAPSHOT_KIND, Run.run_class == "exploratory", Run.status == "succeeded",
                    Run.manifest_hash.is_not(None), counted_runs(),
-                   or_(func.json_extract(Artifact.meta, "$.source_id") == source.id,
-                       func.json_extract(Artifact.meta, "$.source") == source.name))
+                   or_(json_eq(Artifact.meta, "source_id", source.id),
+                       json_eq(Artifact.meta, "source", source.name)))
             .order_by(Run.finished_at.desc(), Run.id, Artifact.id))
     cut = _aware(before)
     offset = 0
@@ -1473,10 +1472,10 @@ async def _probe_calibers(change: Mapping[str, Any]) -> list[str]:
             continue
         async with SessionLocal() as session:
             done = await session.scalar(select(func.count()).select_from(Run).where(
-                Run.origin_kind == ORIGIN, func.json_extract(Run.origin, "$.probe") == 1,
-                func.json_extract(Run.origin, "$.workflow_id") == caliber.workflow_id,
-                func.json_extract(Run.origin, "$.version") == caliber.version,
-                func.json_extract(Run.origin, "$.change") == change.get("id")))
+                Run.origin_kind == ORIGIN, json_flag(Run.origin, "probe"),
+                json_eq(Run.origin, "workflow_id", caliber.workflow_id),
+                json_eq(Run.origin, "version", caliber.version),
+                json_eq(Run.origin, "change", change.get("id"))))
             if done:
                 continue
             latest = (await session.execute(select(Run.input).where(
diff --git a/backend/app/ledger/reconcile.py b/backend/app/ledger/reconcile.py
index db2edfff..ea114515 100644
--- a/backend/app/ledger/reconcile.py
+++ b/backend/app/ledger/reconcile.py
@@ -143,10 +143,10 @@ def actions_of(content: dict[str, Any], names: dict[str, str], hide: Any = None)
 
 async def reconciled_runs(session: Any, run_id: str) -> list[Run]:
     """对这次运行对过的账（origin.source_run 是它），新的在前。"""
-    from sqlalchemy import func
+    from app.db.portable import json_eq
 
     rows = (await session.execute(select(Run).where(
-        Run.origin_kind == ORIGIN, func.json_extract(Run.origin, "$.source_run") == run_id)
+        Run.origin_kind == ORIGIN, json_eq(Run.origin, "source_run", run_id))
         .order_by(Run.created_at.desc()))).scalars()
     return list(rows)
 
diff --git a/backend/app/process/tasks.py b/backend/app/process/tasks.py
index 0080edb5..4d62c7eb 100644
--- a/backend/app/process/tasks.py
+++ b/backend/app/process/tasks.py
@@ -35,6 +35,7 @@ from app.db.base import SessionLocal, utcnow
 from app.db.models import (
     App, Approval, AppVersion, AuditEvent, Group, GroupMember, Run, Task, TaskAssignment, User,
 )
+from app.db.portable import json_text
 from app.engine.lint_process import normalize_policy, parse_duration
 from app.process.events import record
 
@@ -913,7 +914,7 @@ async def tick(now: datetime | None = None) -> list[str]:
     """调度循环每一拍：提醒、升级、超时驳回（永不自动批准）。交回这一拍处理过的待办 id（生效可查：办了哪几条，
     不只是几条；测试按自己造的那条断言，不受同一个库里别的待办影响）。试运行的待办不处理（只显示时限）。"""
     now = now or utcnow()
-    action = func.json_extract(Task.on_timeout, "$.action")
+    action = json_text(Task.on_timeout, "action")
     trial = select(Run.id).where(Run.origin_kind == TRIAL_ORIGIN)
     async with SessionLocal() as session:
         due = list((await session.execute(select(Task.id).where(
diff --git a/backend/pyproject.toml b/backend/pyproject.toml
index d7af0048..dc027c29 100644
--- a/backend/pyproject.toml
+++ b/backend/pyproject.toml
@@ -20,6 +20,9 @@ dependencies = [
     # 所以上限卡到下一个小版本——升级要主动改这里、重新锁、跑一遍测试。
     # 精确版本在 requirements.lock 里
     "langgraph>=1.2.11,<1.3",
+    # 断点的序列化格式就在这个包里（langgraph 只要求 <5，上面那条卡不住它）；SQLite、PostgreSQL 两种断点库
+    # 共用这一份格式，copy-to-postgres 搬断点也靠它前后一致
+    "langgraph-checkpoint>=4.2.0,<4.3",
     "langgraph-checkpoint-sqlite>=3.1.1,<3.2",
     "langchain-core>=1.6.3,<1.7",
     "langchain-anthropic>=1.7.2,<1.8",
@@ -49,6 +52,15 @@ docs = ["pypdf>=5.0", "python-docx>=1.1", "python-pptx>=1.0", "openpyxl>=3.1"]
 # 数据库接入。三个驱动都是 asyncio 原生且免装数据库客户端——
 # oracledb 走 thin 模式，省掉了 Oracle Instant Client 这个历来最劝退的一步。
 db = ["aiomysql>=0.2", "oracledb>=2.0", "asyncpg>=0.30"]
+# 应用自己的库用 PostgreSQL（AGENTLAB_DATABASE_URL=postgresql+asyncpg://…）。应用库走 asyncpg；LangGraph 的断点
+# 走官方的 langgraph-checkpoint-postgres，它只认 psycopg 3 和它的连接池。psycopg 带 binary：wheel 里自带 libpq，
+# 镜像和本机都不用另装 PostgreSQL 客户端。断点格式归 LangGraph 一族管，上限同上卡到下一个小版本
+postgres = [
+    "asyncpg>=0.30",
+    "psycopg[binary]>=3.2,<4",
+    "psycopg-pool>=3.2,<4",
+    "langgraph-checkpoint-postgres>=3.1.2,<3.2",
+]
 
 [build-system]
 requires = ["hatchling"]
diff --git a/backend/pytest.ini b/backend/pytest.ini
index b30d93f3..facc6e1c 100644
--- a/backend/pytest.ini
+++ b/backend/pytest.ini
@@ -3,3 +3,5 @@
 asyncio_mode = auto
 testpaths = tests
 addopts = -q --tb=short
+markers =
+    sqlite_only: 只对 SQLite 应用库成立的测试（数据目录里的库文件、PRAGMA）；AGENTLAB_TEST_DATABASE_URL 跑 PostgreSQL 时跳过
diff --git a/backend/requirements.lock b/backend/requirements.lock
index ee31c969..20b8fb3d 100644
--- a/backend/requirements.lock
+++ b/backend/requirements.lock
@@ -136,9 +136,13 @@ langgraph==1.2.11
     # via agentlab-backend (pyproject.toml)
 langgraph-checkpoint==4.2.0
     # via
+    #   agentlab-backend (pyproject.toml)
     #   langgraph
+    #   langgraph-checkpoint-postgres
     #   langgraph-checkpoint-sqlite
     #   langgraph-prebuilt
+langgraph-checkpoint-postgres==3.1.2
+    # via agentlab-backend (pyproject.toml)
 langgraph-checkpoint-sqlite==3.1.1
     # via agentlab-backend (pyproject.toml)
 langgraph-prebuilt==1.1.0
@@ -167,6 +171,7 @@ oracledb==26.0.0
     # via agentlab-backend (pyproject.toml)
 orjson==3.12.0
     # via
+    #   langgraph-checkpoint-postgres
     #   langgraph-sdk
     #   langsmith
 ormsgpack==1.12.2
@@ -180,6 +185,16 @@ pillow==12.3.0
     # via python-pptx
 pluggy==1.6.0
     # via pytest
+psycopg==3.3.6
+    # via
+    #   agentlab-backend (pyproject.toml)
+    #   langgraph-checkpoint-postgres
+psycopg-binary==3.3.6 ; implementation_name != 'pypy'
+    # via psycopg
+psycopg-pool==3.3.3
+    # via
+    #   agentlab-backend (pyproject.toml)
+    #   langgraph-checkpoint-postgres
 pycparser==3.0 ; implementation_name != 'PyPy' and platform_python_implementation != 'PyPy'
     # via cffi
 pydantic==2.13.5
@@ -294,6 +309,8 @@ typing-extensions==4.16.0
     #   mcp
     #   openai
     #   oracledb
+    #   psycopg
+    #   psycopg-pool
     #   pydantic
     #   pydantic-core
     #   pytest-asyncio
@@ -309,6 +326,8 @@ typing-inspection==0.4.4
     #   mcp
     #   pydantic
     #   pydantic-settings
+tzdata==2026.5 ; sys_platform == 'win32'
+    # via psycopg
 urllib3==2.7.0
     # via requests
 uuid-utils==0.17.1
diff --git a/backend/tests/appdb.py b/backend/tests/appdb.py
new file mode 100644
index 00000000..bf217064
--- /dev/null
+++ b/backend/tests/appdb.py
@@ -0,0 +1,77 @@
+"""测试里另开一条连接直接改应用库：模拟别处（另一个进程、恢复、继续运行）抢在中间提交。
+
+应用库是 SQLite 时用 sqlite3 连数据目录里的 agentlab.db（同以前各处的写法）；是 PostgreSQL 时（AGENTLAB_TEST_DATABASE_URL，
+见 conftest）用 psycopg 连同一个库。SQL 一律用 ? 占位，两种库写成同一句；锁等 5 秒（同以前 sqlite3 的 timeout=5）：
+另一条连接要等的锁正好被调用方拿着的话，等满报错，不会把测试卡死。
+"""
+
+from __future__ import annotations
+
+import re
+from typing import Any
+
+from app.core.config import settings
+
+
+def is_postgres() -> bool:
+    return settings.db_dialect == "postgresql"
+
+
+def _pg_conninfo() -> str:
+    from app.db.urls import libpq_conninfo
+
+    return libpq_conninfo(settings.db_url)
+
+
+def execute(*statements: str | tuple[str, tuple[Any, ...]]) -> None:
+    """在另一条连接上依次执行、一起提交。每一项是 SQL，或者 (SQL, 参数)。"""
+    items = [(s, ()) if isinstance(s, str) else (s[0], tuple(s[1])) for s in statements]
+    if is_postgres():
+        import psycopg
+
+        with psycopg.connect(_pg_conninfo(), options="-c lock_timeout=5000") as conn:
+            for sql, params in items:
+                conn.execute(re.sub(r"\?", "%s", sql), params)
+            conn.commit()
+        return
+    import sqlite3
+
+    db = sqlite3.connect(settings.db_path, timeout=5)
+    try:
+        for sql, params in items:
+            db.execute(sql, params)
+        db.commit()
+    finally:
+        db.close()
+
+
+def query(sql: str, *params: Any) -> list[tuple[Any, ...]]:
+    """在另一条连接上读：看别人这时提交了什么（不是调用方事务里的）。"""
+    if is_postgres():
+        import psycopg
+
+        with psycopg.connect(_pg_conninfo(), options="-c lock_timeout=5000") as conn:
+            return [tuple(r) for r in conn.execute(re.sub(r"\?", "%s", sql), params).fetchall()]
+    import sqlite3
+
+    db = sqlite3.connect(settings.db_path, timeout=5)
+    try:
+        return [tuple(r) for r in db.execute(sql, params).fetchall()]
+    finally:
+        db.close()
+
+
+def refuse_inserts(table: str, condition: str, *, name: str) -> tuple[list[str], list[str]]:
+    """建一个触发器：往 table 插入满足 condition（用 NEW.列 写）的行时报错，报的是完整性错误（IntegrityError），同 SQLite
+    的 RAISE(ABORT)。返回 (建的语句, 删的语句)，各是一串语句，逐条在应用库的连接上执行。
+
+    PostgreSQL 要先建一个触发器函数（plpgsql）再挂上去，错误码给 23000（integrity_constraint_violation）。"""
+    if is_postgres():
+        create = [f"CREATE FUNCTION {name}_fn() RETURNS trigger AS $$ BEGIN IF {condition} THEN "
+                  f"RAISE EXCEPTION 'refused by test' USING ERRCODE = 'integrity_constraint_violation'; END IF; "
+                  f"RETURN NEW; END $$ LANGUAGE plpgsql",
+                  f"CREATE TRIGGER {name} BEFORE INSERT ON {table} FOR EACH ROW EXECUTE FUNCTION {name}_fn()"]
+        drop = [f"DROP TRIGGER IF EXISTS {name} ON {table}", f"DROP FUNCTION IF EXISTS {name}_fn()"]
+        return create, drop
+    return ([f"CREATE TRIGGER {name} BEFORE INSERT ON {table} WHEN {condition} "
+             f"BEGIN SELECT RAISE(ABORT, 'refused by test'); END"], [f"DROP TRIGGER IF EXISTS {name}"])
diff --git a/backend/tests/conftest.py b/backend/tests/conftest.py
index c8f7d71d..cd074b0a 100644
--- a/backend/tests/conftest.py
+++ b/backend/tests/conftest.py
@@ -12,12 +12,58 @@ app.db.base 导入时就按 db_url 建好了。conftest 早于测试模块加载
 
 from __future__ import annotations
 
+import atexit
 import os
 import tempfile
 from pathlib import Path
 
 _TMP = Path(tempfile.mkdtemp(prefix="agentlab-tests-"))
 os.environ["AGENTLAB_DATA_DIR"] = str(_TMP)
+
+
+def _postgres_database(admin_url: str) -> str:
+    """AGENTLAB_TEST_DATABASE_URL 给的是管理用的库：每个 xdist 进程在同一台服务器上建一个自己的空库（库名加进程号后缀，
+    已有的同名库先删掉），进程退出时删掉。返回这个库的地址。scripts/test-postgres.sh 起临时容器、设好这个变量。"""
+    import psycopg
+    from sqlalchemy.engine import make_url
+
+    from app.db.urls import libpq_conninfo, normalize_database_url
+
+    url = make_url(normalize_database_url(admin_url))
+    name = f"{url.database}_{os.environ.get('PYTEST_XDIST_WORKER', 'main')}"
+    admin = libpq_conninfo(url.render_as_string(hide_password=False))
+
+    def run(sql: str) -> None:
+        with psycopg.connect(admin, autocommit=True) as conn:
+            conn.execute(sql)
+
+    run(f'DROP DATABASE IF EXISTS "{name}" WITH (FORCE)')
+    run(f'CREATE DATABASE "{name}"')
+
+    def drop() -> None:
+        try:
+            run(f'DROP DATABASE IF EXISTS "{name}" WITH (FORCE)')
+        except Exception:  # noqa: BLE001 - 服务器先走了（容器已删）就算了
+            pass
+
+    atexit.register(drop)
+    return url.set(database=name).render_as_string(hide_password=False)
+
+
+# 应用库：缺省数据目录里的 SQLite。设了 AGENTLAB_TEST_DATABASE_URL 就跑在 PostgreSQL 上。不管哪种，都盖掉环境和 .env
+# 里可能有的 AGENTLAB_DATABASE_URL / AGENTLAB_CHECKPOINT_URL：测试绝不能连到真在用的库上
+_TEST_PG = os.environ.get("AGENTLAB_TEST_DATABASE_URL", "").strip()
+os.environ["AGENTLAB_CHECKPOINT_URL"] = ""
+os.environ["AGENTLAB_DATABASE_URL"] = _postgres_database(_TEST_PG) if _TEST_PG else ""
+if _TEST_PG:
+    # 每个测试一个事件循环（pytest-asyncio 的缺省），asyncpg 的连接不能跨循环用：引擎先按不用连接池建，
+    # 再换成按事件循环分的池子（tests/pgpool.py），一个测试里的查库照样复用连接
+    os.environ["AGENTLAB_DB_POOL_SIZE"] = "0"
+
+    from app.db.base import engine as _app_engine  # noqa: E402
+    from tests.pgpool import install as _loop_local_pool  # noqa: E402
+
+    _loop_local_pool(_app_engine)
 # 别把真实的 key 带进测试环境
 os.environ.setdefault("AGENTLAB_SECRET_KEY", "test-only-not-a-real-key")
 # 定时任务的调度循环不在测试里起：走 lifespan 的测试不该到点替人发起运行。要测调度的直接调它
@@ -42,7 +88,18 @@ def _prepare_schema():
 
 
 def pytest_report_header(config) -> str:
-    return f"测试数据目录：{_TMP}"
+    where = "PostgreSQL（AGENTLAB_TEST_DATABASE_URL）" if _TEST_PG else "SQLite"
+    return f"测试数据目录：{_TMP}；应用库：{where}"
+
+
+def pytest_collection_modifyitems(config, items) -> None:
+    """标了 sqlite_only 的测试只在应用库是 SQLite 时跑：它们断言的是 SQLite 自己的东西（数据目录里的库文件、PRAGMA）。"""
+    if not _TEST_PG:
+        return
+    skip = pytest.mark.skip(reason="只对 SQLite 应用库成立")
+    for item in items:
+        if "sqlite_only" in item.keywords:
+            item.add_marker(skip)
 
 
 @pytest.fixture(scope="session")
diff --git a/backend/tests/pgpool.py b/backend/tests/pgpool.py
new file mode 100644
index 00000000..ae1b4a65
--- /dev/null
+++ b/backend/tests/pgpool.py
@@ -0,0 +1,123 @@
+"""应用库是 PostgreSQL 时测试用的连接池：每个事件循环一个池子，连接只给建它的那个循环用。
+
+pytest-asyncio 每个测试一个事件循环，TestClient 在自己的线程里另起一个；asyncpg 的连接绑在建它的循环上，换个循环用
+就报「attached to a different loop」。不用连接池（每次查库新建连接）能跑，但一次运行几十次查库，每次多几毫秒，
+合起来让计时类的测试（审批收尾不计时长、反查的时限）在满载时越界——生产上有连接池，没有这笔开销。
+
+这里：连接按建它的循环归池子，取的时候只从当前循环的池子里拿，还回来放回它自己的池子；循环关掉之前（测试结束、
+TestClient 退出）把它池子里的连接在它自己的循环里关掉。只在 conftest 里、AGENTLAB_TEST_DATABASE_URL 时装上，
+生产代码不用它。
+"""
+
+from __future__ import annotations
+
+import asyncio
+import contextlib
+import threading
+import weakref
+from typing import Any
+
+from sqlalchemy.pool import Pool
+
+_LOOP = "agentlab_loop"
+
+
+class LoopLocalPool(Pool):
+    _is_asyncio = True
+
+    def __init__(self, creator: Any, **kw: Any) -> None:
+        super().__init__(creator, **kw)
+        self._idle: weakref.WeakKeyDictionary[asyncio.AbstractEventLoop, list[Any]] = weakref.WeakKeyDictionary()
+        self._lock = threading.Lock()
+
+    @classmethod
+    def replacing(cls, pool: Pool) -> LoopLocalPool:
+        """换掉引擎原来的池子：同一个建连接的函数、同一套连接事件（方言的 on_connect 挂在上面）。"""
+        return cls(pool._creator, recycle=pool._recycle, echo=pool.echo, logging_name=pool._orig_logging_name,
+                   reset_on_return=pool._reset_on_return, pre_ping=False, _dispatch=pool.dispatch,
+                   dialect=pool._dialect)
+
+    def recreate(self) -> LoopLocalPool:
+        return LoopLocalPool.replacing(self)
+
+    def _bucket(self, loop: asyncio.AbstractEventLoop) -> list[Any]:
+        with self._lock:
+            return self._idle.setdefault(loop, [])
+
+    def _do_get(self) -> Any:
+        bucket = self._bucket(asyncio.get_running_loop())
+        with self._lock:
+            if bucket:
+                return bucket.pop()
+        record = self._create_connection()
+        record.info[_LOOP] = weakref.ref(asyncio.get_running_loop())
+        return record
+
+    def _do_return_conn(self, record: Any) -> None:
+        ref = record.info.get(_LOOP)
+        loop = ref() if ref is not None else None
+        if loop is None or loop.is_closed():
+            with contextlib.suppress(Exception):
+                record.close()
+            return
+        bucket = self._bucket(loop)
+        with self._lock:
+            bucket.append(record)
+
+    def take(self, loop: asyncio.AbstractEventLoop) -> list[Any]:
+        """这个循环池子里空闲的连接，取出来（交给调用方在这个循环里关掉）。"""
+        with self._lock:
+            return self._idle.pop(loop, [])
+
+    def dispose(self) -> None:
+        """只关当前循环的：别的循环的连接不能在这里关。没有正在跑的循环时什么都不做（各循环关掉时自己收拾）。"""
+        try:
+            loop = asyncio.get_running_loop()
+        except RuntimeError:
+            return
+        for record in self.take(loop):
+            with contextlib.suppress(Exception):
+                record.close()
+
+    def status(self) -> str:
+        with self._lock:
+            idle = sum(len(v) for v in self._idle.values())
+        return f"LoopLocalPool id:{id(self)} idle:{idle} loops:{len(self._idle)}"
+
+
+def install(engine: Any) -> LoopLocalPool:
+    """把应用库引擎的池子换成 LoopLocalPool，并让每个事件循环关掉之前先关它自己的连接。"""
+    from sqlalchemy.util import greenlet_spawn
+
+    pool = LoopLocalPool.replacing(engine.sync_engine.pool)
+    engine.sync_engine.pool = pool
+
+    async def close_mine(records: list[Any]) -> None:
+        def run() -> None:
+            for record in records:
+                with contextlib.suppress(Exception):
+                    record.close()
+
+        await greenlet_spawn(run)
+
+    base = asyncio.get_event_loop_policy()
+
+    class Policy(type(base)):  # type: ignore[misc]
+        def new_event_loop(self) -> asyncio.AbstractEventLoop:
+            loop = super().new_event_loop()
+            close = loop.close
+
+            def closing() -> None:
+                current = engine.sync_engine.pool
+                if isinstance(current, LoopLocalPool) and not loop.is_closed() and not loop.is_running():
+                    records = current.take(loop)
+                    if records:
+                        with contextlib.suppress(Exception):
+                            loop.run_until_complete(close_mine(records))
+                close()
+
+            loop.close = closing  # type: ignore[method-assign]
+            return loop
+
+    asyncio.set_event_loop_policy(Policy())
+    return pool
diff --git a/backend/tests/test_datasources_upload.py b/backend/tests/test_datasources_upload.py
index 51ca5fb7..30060844 100644
--- a/backend/tests/test_datasources_upload.py
+++ b/backend/tests/test_datasources_upload.py
@@ -556,9 +556,16 @@ async def test_startup_locks_legacy_sources_registered_under_other_spellings(cli
 
 
 def _app_db() -> str:
-    """测试进程实际连着的元数据库（conftest 建的那个）。data_dir 被夹具换过，和 settings.db_path 不是同一个。"""
+    """测试进程实际连着的元数据库（conftest 建的那个）。data_dir 被夹具换过，和 settings.db_path 不是同一个。
+
+    应用库是 PostgreSQL 时没有连着的库文件：拿数据目录里的 agentlab.db 顶上（导入 PostgreSQL 之前留下的那一份，
+    同一批元数据，照样不许登记），先建出这个文件，硬链接、大小写这些变体才有东西可指。"""
     from app.db import base as db_base
 
+    if db_base.engine.dialect.name != "sqlite":
+        settings.db_path.parent.mkdir(parents=True, exist_ok=True)
+        settings.db_path.touch()
+        return str(settings.db_path)
     return str(db_base.engine.url.database)
 
 
diff --git a/backend/tests/test_db_portable.py b/backend/tests/test_db_portable.py
new file mode 100644
index 00000000..7dcbfc11
--- /dev/null
+++ b/backend/tests/test_db_portable.py
@@ -0,0 +1,357 @@
+"""应用库在 SQLite、PostgreSQL 上行为一致（db/portable.py、db/postgres.py、db/base.py 的迁移）。
+
+连着库的那几项在两种库上各跑一遍（scripts/test-postgres.sh 跑 PostgreSQL），断言同一套结果；只看编译结果的不连库；
+PostgreSQL 老库迁移另建一个库（只在 AGENTLAB_TEST_DATABASE_URL 时跑）。全是虚构数据。
+"""
+
+from __future__ import annotations
+
+import os
+import re
+import uuid
+
+import pytest
+from sqlalchemy import func, select, text
+from sqlalchemy.exc import IntegrityError
+from sqlalchemy.schema import CreateTable
+
+from app.db import base as db_base
+from app.db.base import Base, SessionLocal
+from app.db.models import Run, TableRecipe
+from app.db.portable import json_eq, json_flag, json_is_string, json_text, unique_violation
+
+PG = bool(os.environ.get("AGENTLAB_TEST_DATABASE_URL", "").strip())
+
+
+def _pg_dialect():
+    from sqlalchemy.dialects.postgresql.asyncpg import dialect
+
+    from app.db import postgres
+
+    made = dialect()
+    postgres.install(made)
+    return made
+
+
+# --------------------------------------------------------------------------
+# 守着的约定
+# --------------------------------------------------------------------------
+
+
+def test_every_migrated_column_is_in_the_models():
+    """PostgreSQL 上补列的类型取模型里这一列的（db/base._column_ddl）：迁移表里的每一列模型里都得有。"""
+    missing = [(t, c) for t, c, _ in db_base._COLUMN_MIGRATIONS
+               if t not in Base.metadata.tables or c not in Base.metadata.tables[t].c]
+    assert missing == []
+
+
+def test_checkpoint_tables_do_not_clash_with_app_tables():
+    """断点和应用表放在同一个库、同一个 schema：两边的表名不能撞。名字从两个 saver 自己的建表语句里取。"""
+    import inspect as pyinspect
+
+    from langgraph.checkpoint.postgres.base import BasePostgresSaver
+    from langgraph.checkpoint.sqlite.aio import AsyncSqliteSaver
+
+    created = set(re.findall(r"CREATE TABLE IF NOT EXISTS (\w+)", " ".join(BasePostgresSaver.MIGRATIONS)))
+    created |= set(re.findall(r"CREATE TABLE IF NOT EXISTS (\w+)", pyinspect.getsource(AsyncSqliteSaver.setup)))
+    assert {"checkpoints", "checkpoint_blobs", "checkpoint_writes", "checkpoint_migrations"} <= created
+    assert created & set(Base.metadata.tables) == set()
+
+
+def test_postgres_columns_are_unbounded_varchar_bigint_and_json():
+    """应用库上 String(n) 建成不限长的 VARCHAR、Integer 是 BIGINT（自增主键 BIGSERIAL）、JSON 是 json（不是 JSONB：
+    JSONB 会重排对象里的键）、时间是不带时区的 TIMESTAMP。SQLite 上的建表语句不变。"""
+    from sqlalchemy.dialects.sqlite.aiosqlite import dialect as sqlite_dialect
+
+    runs = Base.metadata.tables["runs"]
+    pg = CreateTable(runs).compile(dialect=_pg_dialect()).string
+    assert "id VARCHAR NOT NULL" in pg and "VARCHAR(" not in pg
+    assert "last_seq BIGINT" in pg and "INTEGER" not in pg
+    assert "input JSON NOT NULL" in pg and "JSONB" not in pg
+    assert "created_at TIMESTAMP WITHOUT TIME ZONE NOT NULL" in pg
+    changes = CreateTable(Base.metadata.tables["source_changes"]).compile(dialect=_pg_dialect()).string
+    assert "seq BIGSERIAL NOT NULL" in changes
+    lite = CreateTable(runs).compile(dialect=sqlite_dialect()).string
+    assert "id VARCHAR(32) NOT NULL" in lite and "last_seq INTEGER" in lite and "input JSON NOT NULL" in lite
+
+
+def test_postgres_casts_keep_their_length():
+    """CAST(x AS VARCHAR(n)) 是截断的意思，照旧写长度；只有建表时的列不限长。"""
+    from sqlalchemy import String, cast
+
+    sql = str(select(cast(Run.workflow_name, String(4))).compile(dialect=_pg_dialect()))
+    assert "CAST(runs.workflow_name AS VARCHAR(4))" in sql
+
+
+def test_postgres_orders_nulls_like_sqlite():
+    """SQLite 升序 NULL 在前、降序 NULL 在后：PostgreSQL 上可空列照这个补写，不可空的列、写明了的不动。"""
+    from app.db.models import Task
+
+    sql = str(select(Run.id, func.row_number().over(order_by=Run.started_at).label("n"))
+              .order_by(Run.started_at, Run.finished_at.desc(), Run.created_at.desc(),
+                        Task.due_at.desc().nulls_first(), Task.remind_at.asc().nulls_last())
+              .compile(dialect=_pg_dialect()))
+    assert "OVER (ORDER BY runs.started_at ASC NULLS FIRST)" in sql
+    order = sql.split("ORDER BY", 2)[2]
+    assert "runs.started_at ASC NULLS FIRST" in order
+    assert "runs.finished_at DESC NULLS LAST" in order
+    assert "runs.created_at DESC," in order                       # 不可空：不补
+    assert "tasks.due_at DESC NULLS FIRST" in order and "NULLS FIRST NULLS" not in order
+    assert "tasks.remind_at ASC NULLS LAST" in order
+
+
+def test_postgres_integer_binds_are_bigint():
+    """和 Integer 列比较、写进 Integer 列的参数按 BIGINT 转换，超过 21 亿的值不在半路溢出。"""
+    sql = str(select(Run.id).where(Run.last_seq > 5).compile(dialect=_pg_dialect()))
+    assert "runs.last_seq > $1::BIGINT" in sql
+
+
+# --------------------------------------------------------------------------
+# 连着库：两种库同一套结果
+# --------------------------------------------------------------------------
+
+
+async def _runs(origins: list[dict | None]) -> tuple[str, list[str]]:
+    tag = uuid.uuid4().hex[:12]
+    ids = []
+    async with SessionLocal() as session:
+        for i, origin in enumerate(origins):
+            row = Run(workflow_name=f"便携-{tag}-{i}", origin=origin, input={"question": "虚构的问题"} if i % 2 else
+                      {"question": 7})
+            session.add(row)
+            await session.flush()
+            ids.append(row.id)
+        await session.commit()
+    return tag, ids
+
+
+async def _match(tag: str, *where) -> list[int]:
+    async with SessionLocal() as session:
+        names = (await session.execute(select(Run.workflow_name).where(
+            Run.workflow_name.like(f"便携-{tag}-%"), *where))).scalars().all()
+    return sorted(int(n.rsplit("-", 1)[1]) for n in names)
+
+
+async def test_json_helpers_match_the_same_rows_on_both_databases():
+    tag, _ = await _runs([
+        {"v": 3, "s": "3", "flag": True, "k": "甲"},       # 0
+        {"v": "3", "s": 3, "flag": 1, "k": None},          # 1
+        {"v": 4, "flag": 0, "k": "乙", "uses": ["r-1", "r-22"]},  # 2
+        {"flag": False},                                   # 3
+        {},                                                # 4
+        None,                                              # 5（JSON 的 null）
+    ])
+    # 带类型的相等：数字 3 不等于字符串 "3"
+    assert await _match(tag, json_eq(Run.origin, "v", 3)) == [0]
+    assert await _match(tag, json_eq(Run.origin, "v", "3")) == [1]
+    assert await _match(tag, json_eq(Run.origin, "s", "3")) == [0]
+    # None：没有这个键、或者值是 null
+    assert await _match(tag, json_eq(Run.origin, "k", None)) == [1, 3, 4, 5]
+    # 标记位：true 和非零的数算真
+    assert await _match(tag, json_flag(Run.origin, "flag")) == [0, 1]
+    from sqlalchemy import not_
+
+    assert await _match(tag, not_(json_flag(Run.origin, "flag"))) == [2, 3, 4, 5]
+    # 文本
+    assert await _match(tag, json_text(Run.origin, "k") == "乙") == [2]
+    assert await _match(tag, func.coalesce(json_text(Run.origin, "k"), "").in_(["甲", ""])) == [0, 1, 3, 4, 5]
+    assert await _match(tag, json_text(Run.origin, "uses").contains("r-22", autoescape=True)) == [2]
+    # 是不是字符串：input.question 偶数行是数字、奇数行是字符串
+    assert await _match(tag, json_is_string(Run.input, "question")) == [1, 3, 5]
+
+
+async def test_json_columns_keep_the_order_of_keys():
+    """JSON 列存原文：对象里键的先后读回来不变（JSONB 会重排，应用里按键的先后出列名、出段落的地方就乱了）。"""
+    keys = ["单号", "金额", "电话", "b", "a", "aa"]
+    async with SessionLocal() as session:
+        row = Run(workflow_name="键序", origin={k: i for i, k in enumerate(keys)})
+        session.add(row)
+        await session.commit()
+        rid = row.id
+    async with SessionLocal() as session:
+        got = (await session.execute(select(Run.origin).where(Run.id == rid))).scalar_one()
+    assert list(got) == keys
+
+
+async def test_json_null_and_sql_null_stay_apart():
+    """JSON 列写 None 存的是 JSON 的 null（不是 SQL 的 NULL），两种库一样：按 IS NULL 筛不到它。"""
+    async with SessionLocal() as session:
+        row = Run(workflow_name="空值", origin=None)
+        session.add(row)
+        await session.commit()
+        rid = row.id
+    async with SessionLocal() as session:
+        is_sql_null = (await session.execute(select(Run.origin.is_(None)).where(Run.id == rid))).scalar_one()
+        raw = (await session.execute(text("SELECT CAST(origin AS TEXT) FROM runs WHERE id = :i"), {"i": rid})).scalar_one()
+    assert is_sql_null is False and raw == "null"
+
+
+async def test_long_strings_and_big_integers_are_kept():
+    """String(n) 超长、Integer 过 21 亿：SQLite 照存，PostgreSQL 上也照存（列不限长、是 BIGINT）。"""
+    long_name = "长" * 500                  # workflow_name 是 String(200)
+    big = 5_000_000_000
+    async with SessionLocal() as session:
+        row = Run(workflow_name=long_name, last_seq=big)
+        session.add(row)
+        await session.commit()
+        rid = row.id
+    async with SessionLocal() as session:
+        got = (await session.execute(select(Run.workflow_name, Run.last_seq).where(
+            Run.id == rid, Run.last_seq > big - 1))).one()
+    assert tuple(got) == (long_name, big)
+
+
+async def test_non_finite_floats_in_json_are_written():
+    """JSON 里的 NaN：SQLite 照存；PostgreSQL 的 json 不收，写成 null（同浏览器的 JSON.stringify），不让整条写入失败。"""
+    async with SessionLocal() as session:
+        row = Run(workflow_name="非有限", origin={"x": float("nan"), "y": 1.5, "s": "a\x00b"})
+        session.add(row)
+        await session.commit()
+        rid = row.id
+    async with SessionLocal() as session:
+        got = (await session.execute(select(Run.origin).where(Run.id == rid))).scalar_one()
+    assert got["y"] == 1.5
+    if db_base.engine.dialect.name == "postgresql":
+        assert got["x"] is None and got["s"] == "ab"
+    else:
+        assert got["x"] != got["x"] and got["s"] == "a\x00b"      # NaN、NUL 原样
+
+
+async def test_unique_violation_names_the_table_and_columns():
+    sid = uuid.uuid4().hex
+    async with SessionLocal() as session:
+        session.add(TableRecipe(source_id=sid, seq=1, recipe={}, recipe_sha256="c" * 64))
+        await session.commit()
+        session.add(TableRecipe(source_id=sid, seq=1, recipe={}, recipe_sha256="c" * 64))
+        with pytest.raises(IntegrityError) as caught:
+            await session.commit()
+    assert unique_violation(caught.value, "table_recipes", "source_id", "seq")
+    assert not unique_violation(caught.value, "table_recipes", "source_id")
+    assert not unique_violation(caught.value, "data_sources", "source_id", "seq")
+
+
+async def test_order_by_puts_nulls_where_sqlite_does():
+    tag = uuid.uuid4().hex[:12]
+    from datetime import datetime, timezone
+
+    async with SessionLocal() as session:
+        for i, started in enumerate([datetime(2026, 1, 2, tzinfo=timezone.utc), None,
+                                     datetime(2026, 1, 1, tzinfo=timezone.utc)]):
+            session.add(Run(workflow_name=f"排序-{tag}-{i}", started_at=started))
+        await session.commit()
+    async with SessionLocal() as session:
+        where = Run.workflow_name.like(f"排序-{tag}-%")
+        up = (await session.execute(select(Run.workflow_name).where(where).order_by(Run.started_at))).scalars().all()
+        down = (await session.execute(select(Run.workflow_name).where(where)
+                                      .order_by(Run.started_at.desc()))).scalars().all()
+    assert [n[-1] for n in up] == ["1", "2", "0"]          # 升序：NULL 在前
+    assert [n[-1] for n in down] == ["0", "2", "1"]        # 降序：NULL 在后
+
+
+async def test_timestamps_read_back_as_aware_utc():
+    from datetime import datetime, timedelta, timezone
+
+    local = datetime(2026, 3, 4, 9, 30, tzinfo=timezone(timedelta(hours=8)))
+    async with SessionLocal() as session:
+        row = Run(workflow_name="时区", started_at=local)
+        session.add(row)
+        await session.commit()
+        rid = row.id
+    async with SessionLocal() as session:
+        got = (await session.execute(select(Run.started_at).where(Run.id == rid, Run.started_at == local))).scalar_one()
+    assert got == local and got.tzinfo == timezone.utc and got.hour == 1
+
+
+# --------------------------------------------------------------------------
+# PostgreSQL 上的老库迁移
+# --------------------------------------------------------------------------
+
+
+@pytest.fixture
+def scratch_pg():
+    """同一台服务器上另建一个空库，给迁移测试造「老版本建的库」。只在 PostgreSQL 时有。"""
+    if not PG:
+        pytest.skip("要 AGENTLAB_TEST_DATABASE_URL（scripts/test-postgres.sh）")
+    import psycopg
+    from sqlalchemy import create_engine
+    from sqlalchemy.engine import make_url
+
+    from app.db.urls import libpq_conninfo
+
+    admin = make_url(db_base.settings.db_url)
+    name = f"{admin.database}_mig_{uuid.uuid4().hex[:8]}"
+    conninfo = libpq_conninfo(admin.render_as_string(hide_password=False))
+    with psycopg.connect(conninfo, autocommit=True) as conn:
+        conn.execute(f'CREATE DATABASE "{name}"')
+    url = admin.set(drivername="postgresql+psycopg", database=name)
+    engine = create_engine(url)
+    try:
+        yield engine
+    finally:
+        engine.dispose()
+        with psycopg.connect(conninfo, autocommit=True) as conn:
+            conn.execute(f'DROP DATABASE IF EXISTS "{name}" WITH (FORCE)')
+
+
+def _columns(conn, table: str) -> dict[str, tuple[str, str | None]]:
+    rows = conn.execute(text("SELECT column_name, data_type, column_default FROM information_schema.columns "
+                             "WHERE table_name = :t"), {"t": table}).all()
+    return {r[0]: (r[1], r[2]) for r in rows}
+
+
+def test_old_postgres_databases_get_the_missing_columns_and_indexes(scratch_pg):
+    """老版本建的 PostgreSQL 库（少几列、少索引、有并发留下的重复行）：补上的列类型按模型的、缺省值回填，布尔的缺省是
+    false 不是 0，索引补上，唯一索引建之前先去重；再跑一遍什么都不做。"""
+    with scratch_pg.begin() as conn:
+        conn.execute(text("CREATE TABLE runs (id VARCHAR PRIMARY KEY, workflow_id VARCHAR, version BIGINT, "
+                          "status VARCHAR, last_seq BIGINT)"))
+        conn.execute(text("INSERT INTO runs (id, status, last_seq) VALUES ('r1', 'succeeded', 9)"))
+        conn.execute(text("CREATE TABLE schedules (id VARCHAR PRIMARY KEY, name VARCHAR)"))
+        conn.execute(text("INSERT INTO schedules (id, name) VALUES ('s1', '虚构的定时')"))
+        conn.execute(text("CREATE TABLE conversations (id VARCHAR PRIMARY KEY, kind VARCHAR, archived BOOLEAN, "
+                          "workflow_id VARCHAR, last_active_at TIMESTAMP)"))
+        for cid, at in (("c1", "2026-01-01"), ("c2", "2026-01-02")):
+            conn.execute(text("INSERT INTO conversations (id, kind, archived, last_active_at) "
+                              "VALUES (:i, 'app', false, :at)"), {"i": cid, "at": at})
+        db_base._migrate(conn)
+        db_base._migrate(conn)
+        runs = _columns(conn, "runs")
+        assert runs["options"][0] == "json" and runs["options"][1].startswith("'{}'")
+        assert runs["schedule_id"][0] == "character varying" and runs["manifest_seq"][0] == "bigint"
+        assert runs["started_by"][0] == "character varying"
+        assert conn.execute(text("SELECT CAST(options AS TEXT), run_class FROM runs WHERE id = 'r1'")).one() \
+            == ("{}", "exploratory")
+        schedules = _columns(conn, "schedules")
+        assert schedules["trigger_kind"][1].startswith("'cron'")
+        assert conn.execute(text("SELECT trigger_kind FROM schedules")).scalar_one() == "cron"
+        indexes = {r[0] for r in conn.execute(text("SELECT indexname FROM pg_indexes WHERE tablename = 'runs'"))}
+        assert {"ix_runs_schedule_id", "ix_runs_wf_ver_status"} <= indexes
+        # 同一个人在同一个应用里两段没归档的助手对话：created_by 是迁移补上的列（NULL 不受约束），唯一索引照样建上
+        convs = {r[0] for r in conn.execute(text("SELECT indexname FROM pg_indexes WHERE tablename = 'conversations'"))}
+        assert "ux_conversations_app_owner" in convs
+
+
+def test_old_postgres_duplicates_are_settled_before_the_unique_index(scratch_pg):
+    with scratch_pg.begin() as conn:
+        conn.execute(text("CREATE TABLE conversations (id VARCHAR PRIMARY KEY, kind VARCHAR, archived BOOLEAN, "
+                          "app_id VARCHAR, created_by VARCHAR, last_active_at TIMESTAMP)"))
+        for cid, at in (("c1", "2026-01-01"), ("c2", "2026-01-03"), ("c3", "2026-01-02")):
+            conn.execute(text("INSERT INTO conversations VALUES (:i, 'app', false, 'a1', '甲', :at)"),
+                         {"i": cid, "at": at})
+        db_base._migrate(conn)
+        kept = conn.execute(text("SELECT id FROM conversations WHERE archived = false")).scalars().all()
+        assert kept == ["c2"], "留最近活跃的那一段，别的归档"
+        with pytest.raises(Exception, match="ux_conversations_app_owner"):
+            with conn.begin_nested():
+                conn.execute(text("INSERT INTO conversations VALUES ('c4', 'app', false, 'a1', '甲', '2026-02-01')"))
+
+
+async def test_new_postgres_databases_have_the_partial_unique_indexes():
+    """新库靠 create_all：部分唯一索引在 PostgreSQL 上也是部分索引（postgresql_where），条件里的布尔写成 false。"""
+    if not PG:
+        pytest.skip("要 AGENTLAB_TEST_DATABASE_URL（scripts/test-postgres.sh）")
+    async with db_base.engine.connect() as conn:
+        rows = await conn.execute(text("SELECT indexname, indexdef FROM pg_indexes WHERE indexname LIKE 'ux_%'"))
+        got = {r[0]: r[1] for r in rows}
+    assert "WHERE (((kind)::text = 'app'::text) AND (archived = false))" in got["ux_conversations_app_owner"]
+    assert "WHERE ((status)::text = ANY" in got["ux_catalog_draft_jobs_active"]
diff --git a/backend/tests/test_evidence_judge_api.py b/backend/tests/test_evidence_judge_api.py
index 923aec55..25cea0dd 100644
--- a/backend/tests/test_evidence_judge_api.py
+++ b/backend/tests/test_evidence_judge_api.py
@@ -446,7 +446,7 @@ async def test_a_continue_that_wins_the_row_between_check_and_write_gets_no_even
     """核对过状态、还没写入的那一下，接着跑的条件更新（runner._claim）先提交了：追加判定的条件更新落空，
     照样不记——核对和写入是同一行上的条件更新，不是先读后写。"""
     from app.core.bus import bus
-    from app.core.config import settings
+    from tests import appdb
 
     Models(monkeypatch, verdicts={"新客": "contradicted"})
     row = await finish(weekly(claims="judge"))
@@ -456,12 +456,7 @@ async def test_a_continue_that_wins_the_row_between_check_and_write_gets_no_even
     def claimed_in_between(run_id, value):
         # _append_judged 读完运行、分配序号之前正好调用它：在这里用另一条连接把运行占成 running
         if run_id == row.id:
-            db = sqlite3.connect(settings.db_path, timeout=5)
-            try:
-                db.execute("UPDATE runs SET status = 'running' WHERE id = ?", (row.id,))
-                db.commit()
-            finally:
-                db.close()
+            appdb.execute(("UPDATE runs SET status = 'running' WHERE id = ?", (row.id,)))
         set_seq(run_id, value)
 
     monkeypatch.setattr(bus, "set_seq", claimed_in_between)
diff --git a/backend/tests/test_run_append.py b/backend/tests/test_run_append.py
index e73d5f8d..2032c090 100644
--- a/backend/tests/test_run_append.py
+++ b/backend/tests/test_run_append.py
@@ -16,7 +16,6 @@ from __future__ import annotations
 
 import asyncio
 import json
-import sqlite3
 from collections import Counter
 
 import pytest
@@ -25,7 +24,6 @@ from pydantic import BaseModel
 from sqlalchemy import select
 
 from app.core.bus import bus
-from app.core.config import settings
 from app.core.events import EventType
 from app.db.base import SessionLocal
 from app.db.models import Approval, Run, RunEvent
@@ -34,6 +32,7 @@ from app.engine.context import NodeError
 from app.engine.runner import RunManager, run_manager, verify_manifest
 from app.engine.schema import NodeType
 from app.tools.registry import register
+from tests import appdb
 
 #: Agent 场景里工具真正执行的次数。注册表是进程级的，工具只注册一次，计数按测试清零
 CALLS: list[str] = []
@@ -162,12 +161,7 @@ async def _pending(run_id: str) -> list[Approval]:
 
 def _sql(statement: str, *params) -> None:
     """另开一条连接改库：模拟别处（恢复、继续运行、另一个写入者）抢在中间提交。"""
-    db = sqlite3.connect(settings.db_path, timeout=5)
-    try:
-        db.execute(statement, params)
-        db.commit()
-    finally:
-        db.close()
+    appdb.execute((statement, params))
 
 
 # --------------------------------------------------------------------------
@@ -226,12 +220,7 @@ async def test_a_resume_that_wins_the_row_leaves_nothing_behind(monkeypatch):
 
     def resumed_in_between(run_id, value):
         if run_id == paused.id:
-            db = sqlite3.connect(settings.db_path, timeout=5)
-            try:
-                db.execute("UPDATE runs SET status = 'running' WHERE id = ?", (paused.id,))
-                db.commit()
-            finally:
-                db.close()
+            appdb.execute(("UPDATE runs SET status = 'running' WHERE id = ?", (paused.id,)))
         set_seq(run_id, value)
 
     monkeypatch.setattr(bus, "set_seq", resumed_in_between)
@@ -252,14 +241,9 @@ async def test_events_written_elsewhere_in_between_win(monkeypatch):
 
     def written_in_between(run_id, value):
         if run_id == paused.id:
-            db = sqlite3.connect(settings.db_path, timeout=5)
-            try:
-                db.execute("INSERT INTO run_events (id, run_id, seq, type, node_id, ts, data) "
-                           "VALUES ('elsewhere-1', ?, ?, 'log', NULL, 0, '{}')", (paused.id, taken))
-                db.execute("UPDATE runs SET last_seq = ? WHERE id = ?", (taken, paused.id))
-                db.commit()
-            finally:
-                db.close()
+            appdb.execute(("INSERT INTO run_events (id, run_id, seq, type, node_id, ts, data) "
+                           "VALUES ('elsewhere-1', ?, ?, 'log', NULL, 0, '{}')", (paused.id, taken)),
+                          ("UPDATE runs SET last_seq = ? WHERE id = ?", (taken, paused.id)))
         set_seq(run_id, value)
 
     monkeypatch.setattr(bus, "set_seq", written_in_between)
@@ -352,12 +336,8 @@ async def test_published_only_once_stored_and_never_when_not_written(monkeypatch
 
     async def stored_when_published(event):
         if event.type == EventType.APPROVAL_INQUIRY:
-            db = sqlite3.connect(settings.db_path, timeout=5)
-            try:
-                (count,) = db.execute("SELECT count(*) FROM run_events WHERE run_id = ? AND seq = ?",
-                                      (event.run_id, event.seq)).fetchone()
-            finally:
-                db.close()
+            [(count,)] = appdb.query("SELECT count(*) FROM run_events WHERE run_id = ? AND seq = ?",
+                                     event.run_id, event.seq)
             published.append((event.seq, count))
         await publish(event)
 
@@ -430,12 +410,7 @@ async def test_a_sealed_run_that_changes_in_between_gets_nothing(monkeypatch, ch
 
     def changed_in_between(run_id, value):
         if run_id == final.id:
-            db = sqlite3.connect(settings.db_path, timeout=5)
-            try:
-                db.execute(change, (final.id,))
-                db.commit()
-            finally:
-                db.close()
+            appdb.execute((change, (final.id,)))
         set_seq(run_id, value)
 
     monkeypatch.setattr(bus, "set_seq", changed_in_between)
diff --git a/backend/tests/test_run_launch.py b/backend/tests/test_run_launch.py
index baf0935c..5331592b 100644
--- a/backend/tests/test_run_launch.py
+++ b/backend/tests/test_run_launch.py
@@ -322,15 +322,16 @@ async def test_launch_events_are_written_with_the_run_or_not_at_all():
 
     from app.db.base import engine
     from app.engine.launch import launch_run
+    from tests.appdb import refuse_inserts
 
     lib = await upstream_with_two_versions()
     wf, _ = await workflow(weekly(lib, upgrade_policy="dual"), published=1, versions=(1,))
     before = await _run_count()
     # 口径升版处置那条写不进去。走异步引擎建删触发器：同步连接等写锁时会卡住事件循环，而持锁的正是这个循环里的写入
+    create, drop = refuse_inserts("run_events", "NEW.type = 'caliber.upgrade'", name="refuse_upgrade_note")
     async with engine.begin() as conn:
-        await conn.execute(text(
-            "CREATE TRIGGER refuse_upgrade_note BEFORE INSERT ON run_events WHEN NEW.type = 'caliber.upgrade' "
-            "BEGIN SELECT RAISE(ABORT, 'refused by test'); END"))
+        for sql in create:
+            await conn.execute(text(sql))
     try:
         async with SessionLocal() as session:
             with pytest.raises(IntegrityError):
@@ -338,7 +339,8 @@ async def test_launch_events_are_written_with_the_run_or_not_at_all():
         assert await _run_count() == before, "没写进治理事件，却留下了一条运行"
     finally:
         async with engine.begin() as conn:
-            await conn.execute(text("DROP TRIGGER IF EXISTS refuse_upgrade_note"))
+            for sql in drop:
+                await conn.execute(text(sql))
 
 
 async def test_an_exploratory_launch_takes_the_saved_graph_and_the_run_defaults():
diff --git a/backend/tests/test_run_options.py b/backend/tests/test_run_options.py
index ef456a27..f4e7fa53 100644
--- a/backend/tests/test_run_options.py
+++ b/backend/tests/test_run_options.py
@@ -112,9 +112,11 @@ def test_a_missing_table_is_left_alone():
 
 
 async def test_new_databases_index_schedule_id():
+    from sqlalchemy import inspect
+
     async with app_engine.connect() as conn:
-        names = {row[1] for row in (await conn.execute(text("PRAGMA index_list(runs)"))).all()}
-    assert "ix_runs_schedule_id" in names
+        indexes = await conn.run_sync(lambda sync: inspect(sync).get_indexes("runs"))
+    assert {ix["name"]: ix["column_names"] for ix in indexes}.get("ix_runs_schedule_id") == ["schedule_id"]
 
 
 async def test_a_migrated_row_reads_back_empty_options():
diff --git a/backend/tests/test_run_races.py b/backend/tests/test_run_races.py
index 6e89d179..a7d10951 100644
--- a/backend/tests/test_run_races.py
+++ b/backend/tests/test_run_races.py
@@ -254,11 +254,10 @@ async def test_abandoning_while_the_pause_is_being_recorded(slow, monkeypatch):
 
 async def test_an_approval_closed_just_before_it_is_marked_answered(slow, monkeypatch):
     """放弃恰好提交在「读到这条审批还是 pending」和「把它记成已回复」之间。"""
-    import sqlite3
-
     from sqlalchemy import event
 
     from app.db.base import engine
+    from tests import appdb
 
     run = await run_manager.start(graph=_graph(gate=True), input_payload={"q": "x"})
     await _until(lambda: _is(run.id, "interrupted"))
@@ -268,11 +267,8 @@ async def test_an_approval_closed_just_before_it_is_marked_answered(slow, monkey
     def abandon_first(conn, cursor, statement, params, context, executemany):
         if armed["on"] and statement.lstrip().upper().startswith("UPDATE APPROVALS"):
             armed["on"] = False
-            other = sqlite3.connect(engine.url.database, timeout=5)
-            other.execute("UPDATE approvals SET status='cancelled' WHERE run_id=?", (run.id,))
-            other.execute("UPDATE runs SET status='cancelled' WHERE id=?", (run.id,))
-            other.commit()
-            other.close()
+            appdb.execute(("UPDATE approvals SET status='cancelled' WHERE run_id=?", (run.id,)),
+                          ("UPDATE runs SET status='cancelled' WHERE id=?", (run.id,)))
 
     event.listen(engine.sync_engine, "before_cursor_execute", abandon_first)
     try:
diff --git a/backend/tests/test_table_versions_p2.py b/backend/tests/test_table_versions_p2.py
index bacd95e6..f90bcae8 100644
--- a/backend/tests/test_table_versions_p2.py
+++ b/backend/tests/test_table_versions_p2.py
@@ -23,6 +23,7 @@ from typing import Any
 
 import pytest
 from sqlalchemy import create_engine, select, text
+from sqlalchemy.exc import IntegrityError
 
 from app.core.config import settings
 from app.data import raw_store, recipe_parsers, recipe_types, table_versions
@@ -32,6 +33,7 @@ from app.db.base import SessionLocal, utcnow
 from app.db.models import (
     DataSource, ImportStaging, SourceSnapshot, TableBuild, TableImport, TableRecipe,
 )
+from app.db.portable import unique_violation
 
 
 @pytest.fixture(autouse=True)
@@ -268,8 +270,10 @@ async def test_recipe_seq_is_unique_per_source():
         session.add(TableRecipe(source_id=sid, seq=1, recipe={}, recipe_sha256=RECIPE_SHA))
         await session.commit()
         session.add(TableRecipe(source_id=sid, seq=1, recipe={}, recipe_sha256=RECIPE_SHA))
-        with pytest.raises(Exception, match="UNIQUE"):
+        with pytest.raises(IntegrityError) as caught:
             await session.commit()
+    # 撞的正是 (source_id, seq) 这一条唯一约束（两种库的报错写法不同，按表和列认）
+    assert unique_violation(caught.value, "table_recipes", "source_id", "seq")
 
 
 # --------------------------------------------------------------------------
diff --git a/scripts/test-postgres.sh b/scripts/test-postgres.sh
new file mode 100755
index 00000000..e337afdb
--- /dev/null
+++ b/scripts/test-postgres.sh
@@ -0,0 +1,53 @@
+#!/usr/bin/env bash
+# 后端测试跑在 PostgreSQL 上（应用库和断点库都是 PostgreSQL）：本机 docker 起一个临时的 postgres:16 容器，只绑
+# 127.0.0.1 的随机端口、数据放内存里，跑完（出错、Ctrl+C 也一样）删掉容器，留镜像。
+#
+#   scripts/test-postgres.sh                          全量，-n auto
+#   scripts/test-postgres.sh tests/test_db_portable.py -x   参数原样交给 pytest（给了参数就不再加 -n auto）
+#   PYTHON=/path/to/python scripts/test-postgres.sh   指定装着后端依赖（含 [postgres]、[dev]）的 Python，缺省 python
+#   AGENTLAB_PG_IMAGE=postgres:16 …                   换镜像（要本机已经有，这里不拉）
+#
+# 测试怎么用这个库见 backend/tests/conftest.py：AGENTLAB_TEST_DATABASE_URL 给的是管理用的库，每个 xdist 进程在上面
+# 建自己的库（库名加 _gw0 之类的后缀），测试结束删掉。只对 SQLite 成立的测试标了 sqlite_only，这里跳过。
+# 不碰 scripts/dialect-it.sh 的容器（那边叫 agentlab-dialect-it-*）。
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "$0")/.." && pwd)"
+PY="${PYTHON:-python}"
+IMAGE="${AGENTLAB_PG_IMAGE:-postgres:16}"
+NAME="agentlab-pgtest-$$"
+USER_NAME="agentlab"
+PASS="pgtest-only"
+DB="agentlab_test"
+
+command -v docker >/dev/null || { echo "缺少 docker"; exit 1; }
+docker image inspect "$IMAGE" >/dev/null 2>&1 || { echo "本机没有镜像 ${IMAGE}（这个脚本不拉镜像）：先 docker pull ${IMAGE}"; exit 1; }
+
+cleanup() { docker rm -f "$NAME" >/dev/null 2>&1 || true; }
+trap cleanup EXIT INT TERM
+
+# fsync、同步提交都关掉：测试库用完就扔，不需要落盘的保证。连接数放宽：每个 xdist 进程不用连接池（每个测试一个事件循环），
+# 但同一时刻会开好几条，断点库还各有一个小池子。认证用 trust（只绑 127.0.0.1、用完即删的库）：不用连接池时每次查库都
+# 新建连接，SCRAM 握手一次十几毫秒，trust 三毫秒，一次运行几十次查库，差出来的够让计时类的测试越界
+docker run -d --name "$NAME" -e POSTGRES_USER="$USER_NAME" -e POSTGRES_PASSWORD="$PASS" -e POSTGRES_DB="$DB" \
+  -e POSTGRES_HOST_AUTH_METHOD=trust \
+  -p 127.0.0.1::5432 --tmpfs /var/lib/postgresql/data:rw "$IMAGE" \
+  -c fsync=off -c synchronous_commit=off -c full_page_writes=off -c max_connections=1000 -c shared_buffers=256MB \
+  >/dev/null
+
+for _ in $(seq 1 60); do
+  if docker exec "$NAME" pg_isready -U "$USER_NAME" -d "$DB" -h 127.0.0.1 >/dev/null 2>&1; then break; fi
+  sleep 0.5
+done
+docker exec "$NAME" pg_isready -U "$USER_NAME" -d "$DB" -h 127.0.0.1 >/dev/null || { echo "PostgreSQL 没起来"; docker logs "$NAME" | tail -20; exit 1; }
+PORT="$(docker port "$NAME" 5432/tcp | head -1 | sed 's/.*://')"
+
+export AGENTLAB_TEST_DATABASE_URL="postgresql+asyncpg://$USER_NAME:$PASS@127.0.0.1:$PORT/$DB"
+echo "测试库：127.0.0.1:${PORT}/${DB}（容器 ${NAME}，结束后删除）"
+
+cd "$ROOT/backend"
+args=("$@")
+[ ${#args[@]} -eq 0 ] && args=(-n auto)
+# 同 README「开发与验证」：环境里的密钥不带进测试
+env -u ANTHROPIC_API_KEY -u ANTHROPIC_BASE_URL -u ANTHROPIC_AUTH_TOKEN -u OPENAI_API_KEY \
+  "$PY" -m pytest "${args[@]}"