diff --git a/backend/app/api/v1/module_ai/chat/crud.py b/backend/app/api/v1/module_ai/chat/crud.py
index 72dd6ca..9af532c 100644
--- a/backend/app/api/v1/module_ai/chat/crud.py
+++ b/backend/app/api/v1/module_ai/chat/crud.py
@@ -3,7 +3,6 @@ from typing import Any
 from agno.db.base import SessionType
 from agno.db.mysql import MySQLDb
 from agno.db.postgres import PostgresDb
-from agno.db.sqlite import SqliteDb
 from agno.session.team import TeamSession
 
 from app.config.setting import settings
@@ -34,7 +33,6 @@ class ChatSessionCRUD:
         db_mapping = {
             "mysql": lambda: MySQLDb(db_url=db_uri, db_schema=settings.DATABASE_NAME, create_schema=False),
             "postgres": lambda: PostgresDb(db_url=db_uri, db_schema="public", create_schema=False),
-            "sqlite": lambda: SqliteDb(db_file=db_uri.replace("sqlite:///", "")),
         }
 
         if db_type not in db_mapping:
diff --git a/backend/app/config/setting.py b/backend/app/config/setting.py
index 9600c8c..113f725 100644
--- a/backend/app/config/setting.py
+++ b/backend/app/config/setting.py
@@ -10,7 +10,6 @@ from pydantic_settings import BaseSettings, SettingsConfigDict
 from app.common.enums import EnvironmentEnum
 from app.config.path_conf import ENV_DIR, STATIC_DIR
 
-
 # JWT 开发默认密钥：仅允许 DEV 环境使用，生产命中即拒绝启动
 _DEV_DEFAULT_SECRET_KEY = "dpb-dev-secret-key-do-not-use-in-production"
 
@@ -110,8 +109,8 @@ class Settings(BaseSettings):
     AUTOFETCH: bool | None = None  # AUTOFLUSH 别名（优先级高于 AUTOFLUSH，兼容旧环境变量名）
     EXPIRE_ON_COMMIT: bool = False  # 是否在提交时过期
 
-    # 数据库连接（生产 PostgreSQL；测试套件用 SQLite）
-    DATABASE_TYPE: Literal["postgres", "sqlite"] = "postgres"
+    # 数据库连接（开发与生产统一 PostgreSQL）
+    DATABASE_TYPE: Literal["postgres"] = "postgres"
     DATABASE_HOST: str = "localhost"
     DATABASE_PORT: int = 5432
     DATABASE_USER: str = "dpb"
@@ -305,19 +304,11 @@ class Settings(BaseSettings):
 
     @property
     def ASYNC_DB_URI(self) -> str:
-        if self.DATABASE_TYPE == "postgres":
-            db_connect = f"postgresql+asyncpg://{self.DATABASE_USER}:{quote_plus(self.DATABASE_PASSWORD)}@{self.DATABASE_HOST}:{self.DATABASE_PORT}/{self.DATABASE_NAME}"
-        else:
-            db_connect = f"sqlite+aiosqlite:///{self.DATABASE_NAME}.db"
-        return db_connect
+        return f"postgresql+asyncpg://{self.DATABASE_USER}:{quote_plus(self.DATABASE_PASSWORD)}@{self.DATABASE_HOST}:{self.DATABASE_PORT}/{self.DATABASE_NAME}"
 
     @property
     def DB_URI(self) -> str:
-        if self.DATABASE_TYPE == "postgres":
-            db_connect = f"postgresql+psycopg://{self.DATABASE_USER}:{quote_plus(self.DATABASE_PASSWORD)}@{self.DATABASE_HOST}:{self.DATABASE_PORT}/{self.DATABASE_NAME}"
-        else:
-            db_connect = f"sqlite:///{self.DATABASE_NAME}.db"
-        return db_connect
+        return f"postgresql+psycopg://{self.DATABASE_USER}:{quote_plus(self.DATABASE_PASSWORD)}@{self.DATABASE_HOST}:{self.DATABASE_PORT}/{self.DATABASE_NAME}"
 
     @property
     def FASTAPI_CONFIG(self) -> dict[str, Any]:
diff --git a/backend/app/core/database.py b/backend/app/core/database.py
index ca3e5f8..665a3e1 100644
--- a/backend/app/core/database.py
+++ b/backend/app/core/database.py
@@ -49,29 +49,19 @@ def create_async_engine_and_session(db_url: str = settings.ASYNC_DB_URI) -> tupl
     - tuple[AsyncEngine, async_sessionmaker[AsyncSession]]: 异步数据库引擎和会话工厂。
     """
     try:
-        # 异步数据库引擎
-        if settings.DATABASE_TYPE == "sqlite":
-            async_engine = create_async_engine(
-                url=db_url,
-                echo=settings.DATABASE_ECHO,
-                echo_pool=settings.ECHO_POOL,
-                pool_pre_ping=settings.POOL_PRE_PING,
-                future=settings.FUTURE,
-                pool_recycle=settings.POOL_RECYCLE,
-            )
-        else:
-            async_engine = create_async_engine(
-                url=db_url,
-                echo=settings.DATABASE_ECHO,
-                echo_pool=settings.ECHO_POOL,
-                pool_pre_ping=settings.POOL_PRE_PING,
-                future=settings.FUTURE,
-                pool_recycle=settings.POOL_RECYCLE,
-                pool_size=settings.POOL_SIZE,
-                max_overflow=settings.MAX_OVERFLOW,
-                pool_timeout=settings.POOL_TIMEOUT,
-                pool_use_lifo=settings.POOL_USE_LIFO,
-            )
+        # 异步数据库引擎（统一 PostgreSQL 连接池参数）
+        async_engine = create_async_engine(
+            url=db_url,
+            echo=settings.DATABASE_ECHO,
+            echo_pool=settings.ECHO_POOL,
+            pool_pre_ping=settings.POOL_PRE_PING,
+            future=settings.FUTURE,
+            pool_recycle=settings.POOL_RECYCLE,
+            pool_size=settings.POOL_SIZE,
+            max_overflow=settings.MAX_OVERFLOW,
+            pool_timeout=settings.POOL_TIMEOUT,
+            pool_use_lifo=settings.POOL_USE_LIFO,
+        )
     except Exception as e:
         logger.error(f"❌ 数据库连接失败 {e}")
         raise
diff --git a/backend/app/utils/number_gen.py b/backend/app/utils/number_gen.py
index 97f19db..0328431 100644
--- a/backend/app/utils/number_gen.py
+++ b/backend/app/utils/number_gen.py
@@ -7,7 +7,7 @@
 存量数据迁移：首次使用某序列名时由 seed_fn（服务端传入）从既有记录推算
 起始号（原扫描逻辑），此后全部走原子递增，不再扫描。
 """
-from typing import Any, Awaitable, Callable
+from collections.abc import Awaitable, Callable
 
 from sqlalchemy import select, text
 from sqlalchemy.ext.asyncio import AsyncSession
@@ -23,10 +23,6 @@ class NumberGenService:
 
     @staticmethod
     async def _acquire_lock(db: AsyncSession, name: str) -> None:
-        from app.config.setting import settings
-
-        if settings.DATABASE_TYPE != "postgres":
-            return  # sqlite 测试库无 advisory lock，退化为普通自增（单进程无并发竞争）
         # hashtextextended 对文本做稳定 64 位哈希，同名序列恒映射同一把锁
         await db.execute(text("SELECT pg_advisory_xact_lock(hashtextextended(:n, 0))"), {"n": name})
 
diff --git a/backend/pyproject.toml b/backend/pyproject.toml
index 66282ad..3d835f5 100644
--- a/backend/pyproject.toml
+++ b/backend/pyproject.toml
@@ -43,15 +43,13 @@ postgres = ["asyncpg==0.31.0"]
 
 [dependency-groups]
 dev = [
-    "aiosqlite==0.22.1",      # 测试：SQLite 内存库（conftest 固定 DATABASE_TYPE=sqlite，勿移除）
-    "fakeredis>=2.21.0,<3",   # 测试：内存 Redis，配合 TESTING
     "pytest==9.0.2",
     "pytest-asyncio>=0.24.0",  # 异步测试支持
     "ruff==0.14.13",          # 代码检查/格式化
 ]
 
 [tool.uv]
-default-groups = ["dev"]     # 本地 uv sync 含 dev；生产 pip -r requirements.txt 不含 pytest/ruff/fakeredis
+default-groups = ["dev"]     # 本地 uv sync 含 dev；生产 pip -r requirements.txt 不含 pytest/ruff
 
 [[tool.uv.index]]
 name = "tuna"
@@ -118,7 +116,7 @@ ignore = [
 ]
 
 [tool.ruff.lint.per-file-ignores]
-"tests/conftest.py" = ["E402"]  # 先设置 TESTING/SQLite 环境再 import 应用
+"tests/conftest.py" = ["E402"]  # 先设置 TESTING/PostgreSQL 环境再 import 应用
 
 [tool.ruff.format]
 docstring-code-format = true
diff --git a/backend/requirements.txt b/backend/requirements.txt
index 0a65db7..c5fd087 100644
--- a/backend/requirements.txt
+++ b/backend/requirements.txt
@@ -1,4 +1,4 @@
-# 与 pyproject.toml [project] dependencies 一致（生产 pip；不含 dev 组：pytest / ruff / fakeredis）
+# 与 pyproject.toml [project] dependencies 一致（生产 pip；不含 dev 组：pytest / ruff）
 agno==2.5.8                            # AI agent框架
 aiofiles==24.1.0                       # 文件操作
 alembic==1.18.4                        # 数据库迁移
diff --git a/backend/tests/test_stat_analysis_tc.py b/backend/tests/test_stat_analysis_tc.py
index f052c45..45d5881 100644
--- a/backend/tests/test_stat_analysis_tc.py
+++ b/backend/tests/test_stat_analysis_tc.py
@@ -6,9 +6,9 @@
 本包装层以 subprocess 顺序调用这些脚本，断言 rc==0 —— 与 run_regression.py 的执行契约一致。
 
 关键点：
-- 全部基于真实 PG16 + Redis（本工程无 SQLite），仅当探测到 PG/Redis 可达才跑，否则 skipif 跳过。
-- 不 import 任何 app 模块（避免被 conftest 的 sqlite 环境污染）；subprocess env 显式构建：
-  剥掉 conftest 注入的 DATABASE_TYPE/DATABASE_NAME/POOL_SIZE/MAX_OVERFLOW/CAPTCHA_ENABLE，
+- 全部基于真实 PG16 + Redis，仅当探测到 PG/Redis 可达才跑，否则 skipif 跳过。
+- 不 import 任何 app 模块（测试库生命周期由 conftest 管理，与统计引擎 tc 独立）；subprocess env 显式构建：
+  清空可能残留的 DATABASE_*/REDIS_*/POOL_*/CAPTCHA_ENABLE 等连接变量，
   置 ENVIRONMENT=dev / DATABASE_TYPE=postgres / PYTHONPATH=backend / PYTHONUTF8=1，
   再并入从 backend/env/.env.dev 解析的真实连接值（可被 TC_CI_* 覆盖，用于验证 skipif 路径）。
 - 标记 pg（pyproject 已注册），`pytest -m pg` 只跑本组；run_ci.py 的验收门即此命令。
@@ -118,7 +118,7 @@ def pg_ready() -> tuple[bool, bool, str]:
 
 
 def _sub_env() -> dict:
-    """显式构建子进程环境：剥掉 conftest 注入的 sqlite 变量，置真实 PG/Redis 连接。"""
+    """显式构建子进程环境：清空可能残留的连接变量，置真实 PG/Redis 连接。"""
     env = dict(os.environ)
     for k in ("DATABASE_TYPE", "DATABASE_NAME", "POOL_SIZE", "MAX_OVERFLOW",
               "CAPTCHA_ENABLE", "ENVIRONMENT", "PYTHONPATH", "PYTHONIOENCODING"):
diff --git a/backend/uv.lock b/backend/uv.lock
index 11afa79..0b62e2d 100644
--- a/backend/uv.lock
+++ b/backend/uv.lock
@@ -46,15 +46,6 @@ wheels = [
     { url = "https://pypi.tuna.tsinghua.edu.cn/packages/a5/45/30bb92d442636f570cb5651bc661f52b610e2eec3f891a5dc3a4c3667db0/aiofiles-24.1.0-py3-none-any.whl", hash = "sha256:b4ec55f4195e3eb5d7abd1bf7e061763e864dd4954231fb8539a0ef8bb8260e5", size = 15896, upload-time = "2024-06-24T11:02:01.529Z" },
 ]
 
-[[package]]
-name = "aiosqlite"
-version = "0.22.1"
-source = { registry = "https://pypi.tuna.tsinghua.edu.cn/simple" }
-sdist = { url = "https://pypi.tuna.tsinghua.edu.cn/packages/4e/8a/64761f4005f17809769d23e518d915db74e6310474e733e3593cfc854ef1/aiosqlite-0.22.1.tar.gz", hash = "sha256:043e0bd78d32888c0a9ca90fc788b38796843360c855a7262a532813133a0650", size = 14821, upload-time = "2025-12-23T19:25:43.997Z" }
-wheels = [
-    { url = "https://pypi.tuna.tsinghua.edu.cn/packages/00/b7/e3bf5133d697a08128598c8d0abc5e16377b51465a33756de24fa7dee953/aiosqlite-0.22.1-py3-none-any.whl", hash = "sha256:21c002eb13823fad740196c5a2e9d8e62f6243bd9e7e4a1f87fb5e44ecb4fceb", size = 17405, upload-time = "2025-12-23T19:25:42.139Z" },
-]
-
 [[package]]
 name = "alembic"
 version = "1.18.4"
@@ -197,8 +188,6 @@ postgres = [
 
 [package.dev-dependencies]
 dev = [
-    { name = "aiosqlite" },
-    { name = "fakeredis" },
     { name = "pytest" },
     { name = "pytest-asyncio" },
     { name = "ruff" },
@@ -243,8 +232,6 @@ provides-extras = ["postgres"]
 
 [package.metadata.requires-dev]
 dev = [
-    { name = "aiosqlite", specifier = "==0.22.1" },
-    { name = "fakeredis", specifier = ">=2.21.0,<3" },
     { name = "pytest", specifier = "==9.0.2" },
     { name = "pytest-asyncio", specifier = ">=0.24.0" },
     { name = "ruff", specifier = "==0.14.13" },
@@ -353,19 +340,6 @@ wheels = [
     { url = "https://pypi.tuna.tsinghua.edu.cn/packages/c1/8b/5fe2cc11fee489817272089c4203e679c63b570a5aaeb18d852ae3cbba6a/et_xmlfile-2.0.0-py3-none-any.whl", hash = "sha256:7a91720bc756843502c3b7504c77b8fe44217c85c537d85037f0f536151b2caa", size = 18059, upload-time = "2024-10-25T17:25:39.051Z" },
 ]
 
-[[package]]
-name = "fakeredis"
-version = "2.34.1"
-source = { registry = "https://pypi.tuna.tsinghua.edu.cn/simple" }
-dependencies = [
-    { name = "redis" },
-    { name = "sortedcontainers" },
-]
-sdist = { url = "https://pypi.tuna.tsinghua.edu.cn/packages/11/40/fd09efa66205eb32253d2b2ebc63537281384d2040f0a88bcd2289e120e4/fakeredis-2.34.1.tar.gz", hash = "sha256:4ff55606982972eecce3ab410e03d746c11fe5deda6381d913641fbd8865ea9b", size = 177315, upload-time = "2026-02-25T13:17:51.315Z" }
-wheels = [
-    { url = "https://pypi.tuna.tsinghua.edu.cn/packages/49/b5/82f89307d0d769cd9bf46a54fb9136be08e4e57c5570ae421db4c9a2ba62/fakeredis-2.34.1-py3-none-any.whl", hash = "sha256:0107ec99d48913e7eec2a5e3e2403d1bd5f8aa6489d1a634571b975289c48f12", size = 122160, upload-time = "2026-02-25T13:17:49.701Z" },
-]
-
 [[package]]
 name = "fastapi"
 version = "0.138.2"
@@ -1251,15 +1225,6 @@ wheels = [
     { url = "https://pypi.tuna.tsinghua.edu.cn/packages/e9/44/75a9c9421471a6c4805dbf2356f7c181a29c1879239abab1ea2cc8f38b40/sniffio-1.3.1-py3-none-any.whl", hash = "sha256:2f6da418d1f1e0fddd844478f41680e794e6051915791a034ff65e5f100525a2", size = 10235, upload-time = "2024-02-25T23:20:01.196Z" },
 ]
 
-[[package]]
-name = "sortedcontainers"
-version = "2.4.0"
-source = { registry = "https://pypi.tuna.tsinghua.edu.cn/simple" }
-sdist = { url = "https://pypi.tuna.tsinghua.edu.cn/packages/e8/c4/ba2f8066cceb6f23394729afe52f3bf7adec04bf9ed2c820b39e19299111/sortedcontainers-2.4.0.tar.gz", hash = "sha256:25caa5a06cc30b6b83d11423433f65d1f9d76c4c6a0c90e3379eaa43b9bfdb88", size = 30594, upload-time = "2021-05-16T22:03:42.897Z" }
-wheels = [
-    { url = "https://pypi.tuna.tsinghua.edu.cn/packages/32/46/9cb0e58b2deb7f82b84065f37f3bffeb12413f947f9388e4cac22c4621ce/sortedcontainers-2.4.0-py2.py3-none-any.whl", hash = "sha256:a163dcaede0f1c021485e957a39245190e74249897e2ae4b2aa38595db237ee0", size = 29575, upload-time = "2021-05-16T22:03:41.177Z" },
-]
-
 [[package]]
 name = "sqlalchemy"
 version = "2.0.51"