diff --git a/backend/app/api/api_v1/routers/auth.py b/backend/app/api/api_v1/routers/auth.py
index 3cb2847..d880a10 100644
--- a/backend/app/api/api_v1/routers/auth.py
+++ b/backend/app/api/api_v1/routers/auth.py
@@ -1,26 +1,35 @@
-from fastapi.security import OAuth2PasswordRequestForm
+
+from fastapi import Form
+from fastapi.security import OAuth2PasswordBearer, OAuth2PasswordRequestForm
 from fastapi import APIRouter, Depends, HTTPException, status
 from datetime import timedelta
 
-from app.db.session import get_db
-from app.core import security
 from app.core.auth import authenticate_user, sign_up_new_user
+from app.core import security,tenantCacheService
+from app.core.dbmanager import get_db
+from sqlalchemy.orm  import Session
 
 auth_router = r = APIRouter()
 
 
 @r.post("/token")
-async def login(
-    db=Depends(get_db), form_data: OAuth2PasswordRequestForm = Depends()
-):
-    user = authenticate_user(db, form_data.username, form_data.password)
-    if not user:
+async def login(db:Session= Depends(get_db) ,form_data: OAuth2PasswordRequestForm = Depends()):
+    if not db :
         raise HTTPException(
             status_code=status.HTTP_401_UNAUTHORIZED,
             detail="Incorrect username or password",
             headers={"WWW-Authenticate": "Bearer"},
         )
 
+    user = authenticate_user(db, form_data.username, form_data.password)
+
+    if not user:
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="abcIncorrect username or password",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+    
     access_token_expires = timedelta(
         minutes=security.ACCESS_TOKEN_EXPIRE_MINUTES
     )
@@ -33,7 +42,7 @@ async def login(
         permissions =";".join(list(set(perlst)))
     
     access_token = security.create_access_token(
-        data={"sub": user.id, "roles":roles,"permissions": permissions ,},
+        data={"sub": user.id,"roles":roles,"permissions": permissions,"tenant":user.tenantid,},
         expires_delta=access_token_expires,
     )
 
diff --git a/backend/app/api/api_v1/routers/kintone.py b/backend/app/api/api_v1/routers/kintone.py
index 57c27c4..947c50b 100644
--- a/backend/app/api/api_v1/routers/kintone.py
+++ b/backend/app/api/api_v1/routers/kintone.py
@@ -8,7 +8,7 @@ import deepdiff
 import app.core.config as config
 import os
 from pathlib import Path
-from app.db.session import SessionLocal
+from app.core.dbmanager import get_db
 from app.db.crud import get_flows_by_app,get_kintoneformat
 from app.core.auth import get_current_active_user,get_current_user
 from app.core.apiexception import APIException
@@ -17,15 +17,15 @@ from app.db.cruddb import domainService
 kinton_router = r = APIRouter()
 
 def getkintoneenv(user = Depends(get_current_user)):
-    db = SessionLocal()
+    db = get_db(user.tenantid) #SessionLocal()
     domain = domainService.get_default_domain(db,user.id) #get_activedomain(db, user.id)
     db.close()
     kintoneevn = config.KINTONE_ENV(domain)
     return kintoneevn
     
 
-def getkintoneformat():
-    db = SessionLocal()
+def getkintoneformat(user = Depends(get_current_user)):
+    db = get_db(user.tenantid)#SessionLocal()
     formats = get_kintoneformat(db)
     db.close()
     return formats
diff --git a/backend/app/api/api_v1/routers/platform.py b/backend/app/api/api_v1/routers/platform.py
index fdc7d0f..d9b577e 100644
--- a/backend/app/api/api_v1/routers/platform.py
+++ b/backend/app/api/api_v1/routers/platform.py
@@ -2,8 +2,8 @@ from http import HTTPStatus
 from fastapi import Query, Request,Depends, APIRouter, UploadFile,HTTPException,File
 from fastapi.responses import JSONResponse
 # from app.core.operation import log_operation
-from app.db import Base,engine
-from app.db.session import get_db
+# from app.db import Base,engine
+from app.core.dbmanager import get_db
 from app.db.crud import *
 from app.db.schemas import *
 from typing import List, Optional
@@ -15,7 +15,7 @@ from app.db.cruddb import domainService,appService
 
 import httpx
 import app.core.config as config
-from app.core import domainCacheService
+from app.core import domainCacheService,tenantCacheService
 
 platform_router = r = APIRouter()
 
diff --git a/backend/app/api/api_v1/routers/users.py b/backend/app/api/api_v1/routers/users.py
index 7d8a0c8..0a4799f 100644
--- a/backend/app/api/api_v1/routers/users.py
+++ b/backend/app/api/api_v1/routers/users.py
@@ -2,7 +2,7 @@ from fastapi import APIRouter, Request, Depends, Response, Security, encoders
 import typing as t
 from app.core.common import ApiReturnModel,ApiReturnPage
 from app.core.apiexception import APIException
-from app.db.session import get_db
+from app.core.dbmanager import get_db
 from app.db.crud import (
     get_allusers,
     get_users,
@@ -16,6 +16,7 @@ from app.db.crud import (
 from app.db.schemas import UserCreate, UserEdit, User, UserOut,RoleBase,Permission
 from app.core.auth import get_current_user,get_current_active_user, get_current_active_superuser
 from app.db.cruddb import userService
+from app.core import tenantCacheService
 
 users_router = r = APIRouter()
 
diff --git a/backend/app/core/__init__.py b/backend/app/core/__init__.py
index 21b6db6..4b75eb9 100644
--- a/backend/app/core/__init__.py
+++ b/backend/app/core/__init__.py
@@ -1 +1,2 @@
-from app.core.cache import domainCacheService
\ No newline at end of file
+from app.core.cache import domainCacheService
+from app.core.cache import tenantCacheService
\ No newline at end of file
diff --git a/backend/app/core/apiexception.py b/backend/app/core/apiexception.py
index 3183ccb..81a102f 100644
--- a/backend/app/core/apiexception.py
+++ b/backend/app/core/apiexception.py
@@ -1,7 +1,7 @@
-from fastapi import HTTPException, status
+from fastapi import HTTPException, status,Depends
 import httpx
 from app.db.schemas import ErrorCreate
-from app.db.session import SessionLocal
+from app.db.session import get_tenant_db
 from app.db.crud import create_log
 
 class APIException(Exception):
@@ -31,9 +31,9 @@ class APIException(Exception):
         self.error = ErrorCreate(location=location, title=title, content=content)
         super().__init__(self.error)
 
-def writedblog(exc: APIException):
-    db = SessionLocal()
-    try:
-        create_log(db,exc.error)
-    finally:
-        db.close()
\ No newline at end of file
+def writedblog(exc: APIException,db = Depends(get_tenant_db())):
+    #db = SessionLocal()
+    #try:
+    create_log(db,exc.error)
+    #finally:
+       #db.close()
\ No newline at end of file
diff --git a/backend/app/core/auth.py b/backend/app/core/auth.py
index 7bb4ee1..23c6231 100644
--- a/backend/app/core/auth.py
+++ b/backend/app/core/auth.py
@@ -3,13 +3,14 @@ import jwt
 from fastapi import Depends, HTTPException, Request, Security, status
 from jwt import PyJWTError
 
-from app.db import models, schemas, session
+from app.db import models, schemas
 from app.db.crud import get_user_by_email, create_user,get_user
 from app.core import security
 from app.db.cruddb import userService
+from app.core.dbmanager import get_db
 
 async def get_current_user(security_scopes: SecurityScopes,
-    db=Depends(session.get_db), token: str = Depends(security.oauth2_scheme)
+    db=Depends(get_db), token: str = Depends(security.oauth2_scheme)
 ):
     credentials_exception = HTTPException(
         status_code=status.HTTP_401_UNAUTHORIZED,
@@ -17,7 +18,6 @@ async def get_current_user(security_scopes: SecurityScopes,
         headers={"WWW-Authenticate": "Bearer"},
     )
     try:
-
         payload = jwt.decode(
             token, security.SECRET_KEY, algorithms=[security.ALGORITHM]
         )
@@ -25,6 +25,10 @@ async def get_current_user(security_scopes: SecurityScopes,
         if id is None:
             raise credentials_exception
 
+        tenant:str = payload.get("tenant")
+        if tenant is None:
+            raise credentials_exception
+        
         permissions: str = payload.get("permissions")
         if not permissions =="ALL":
             for scope in security_scopes.scopes:
@@ -59,11 +63,11 @@ async def get_current_active_superuser(
 
 
 def authenticate_user(db, email: str, password: str):
-    user = get_user_by_email(db, email)
+    user = userService.get_user_by_email(db,email) #get_user_by_email(db, email)
     if not user:
-        return False
+        return None
     if not security.verify_password(password, user.hashed_password):
-        return False
+        return None
     return user
 
 
diff --git a/backend/app/core/cache.py b/backend/app/core/cache.py
index da3f624..7843d17 100644
--- a/backend/app/core/cache.py
+++ b/backend/app/core/cache.py
@@ -2,6 +2,7 @@ import time
 from typing import Any
 from sqlalchemy.orm import Session
 from app.db.cruddb import domainService
+from app.db.cruddb import tenantService
 
 class MemoryCache:
     def __init__(self, max_cache_size: int = 100, ttl: int = 60):
@@ -52,4 +53,19 @@ class domainCache:
     def clear_default_domainurl(self):
         self.memoryCache.clear()
 
-domainCacheService =domainCache()
\ No newline at end of file
+domainCacheService =domainCache()
+
+
+class tenantCache:
+    
+    def __init__(self):
+        self.memoryCache = MemoryCache(max_cache_size=50, ttl=120)
+    
+    def get_tenant_db(self,db: Session, tenantid: str):
+        if not self.memoryCache.get(f"TENANT_{tenantid}"):
+            tenant = tenantService.get_tenant(db,tenantid)
+            if tenant:
+                self.memoryCache.set(f"TENANT_{tenantid}",tenant.db)
+        return self.memoryCache.get(f"TENANT_{tenantid}")
+
+tenantCacheService =tenantCache()
\ No newline at end of file
diff --git a/backend/app/core/dbmanager.py b/backend/app/core/dbmanager.py
new file mode 100644
index 0000000..18dcb22
--- /dev/null
+++ b/backend/app/core/dbmanager.py
@@ -0,0 +1,12 @@
+
+from fastapi import Depends
+from app.db.session import get_tenant_db,get_user_db
+from app.core import tenantCacheService
+
+def get_db(tenant:str = "1",tenantdb = Depends(get_tenant_db)):
+    db_url = tenantCacheService.get_tenant_db(tenantdb,tenant)
+    db =  get_user_db(db_url)
+    try:
+        yield db  
+    finally:
+        db.close() 
diff --git a/backend/app/db/cruddb/__init__.py b/backend/app/db/cruddb/__init__.py
index cca96c5..a41d305 100644
--- a/backend/app/db/cruddb/__init__.py
+++ b/backend/app/db/cruddb/__init__.py
@@ -1,3 +1,4 @@
 from app.db.cruddb.dbuser import userService
 from app.db.cruddb.dbdomain import domainService
-from app.db.cruddb.dbapp import appService
\ No newline at end of file
+from app.db.cruddb.dbapp import appService
+from app.db.cruddb.dbtenant import tenantService
\ No newline at end of file
diff --git a/backend/app/db/cruddb/dbtenant.py b/backend/app/db/cruddb/dbtenant.py
new file mode 100644
index 0000000..9cdaa62
--- /dev/null
+++ b/backend/app/db/cruddb/dbtenant.py
@@ -0,0 +1,13 @@
+from app.db.cruddb.crudbase import crudbase
+from app.db import models, schemas
+from sqlalchemy.orm import Session
+
+class dbtenant(crudbase):
+    def __init__(self):
+        super().__init__(model=models.Tenant)
+
+    def get_tenant(sefl,db:Session,tenantid: str):
+        tenant = db.execute(super().get_by_conditions({"tenantid":tenantid})).scalars().first()
+        return tenant
+
+tenantService = dbtenant() 
\ No newline at end of file
diff --git a/backend/app/db/models.py b/backend/app/db/models.py
index 7b997ff..3dbe8fc 100644
--- a/backend/app/db/models.py
+++ b/backend/app/db/models.py
@@ -1,7 +1,7 @@
 from sqlalchemy import Boolean, Column, Integer, String, DateTime,ForeignKey,Table
 from sqlalchemy.orm import Mapped,relationship,as_declarative,mapped_column
 from datetime import datetime
-from app.db.session import Base
+from app.db  import Base
 from app.core.security import chacha20Decrypt
 
 @as_declarative()
@@ -34,6 +34,7 @@ class User(Base):
     hashed_password = mapped_column(String(200), nullable=False)
     is_active = mapped_column(Boolean, default=True)
     is_superuser = mapped_column(Boolean, default=False)
+    tenantid = mapped_column(String(100))
     createuserid = mapped_column(Integer,ForeignKey("user.id"))
     updateuserid = mapped_column(Integer,ForeignKey("user.id"))
     createuser = relationship('User',foreign_keys=[createuserid]) 
@@ -148,6 +149,7 @@ class Tenant(Base):
     licence  = mapped_column(String(200)) 
     startdate = mapped_column(DateTime)
     enddate = mapped_column(DateTime) 
+    db = mapped_column(String(200))
 
 
 class Domain(Base):
diff --git a/backend/app/db/schemas.py b/backend/app/db/schemas.py
index ca75ae1..7e187ff 100644
--- a/backend/app/db/schemas.py
+++ b/backend/app/db/schemas.py
@@ -51,6 +51,7 @@ class UserCreate(UserBase):
     last_name: str
     is_active:bool
     is_superuser:bool
+    tenantid:t.Optional[str] = "1"
     createuserid:t.Optional[int] = None
     updateuserid:t.Optional[int] = None
 
diff --git a/backend/app/db/session.py b/backend/app/db/session.py
index 148c9a4..3e59821 100644
--- a/backend/app/db/session.py
+++ b/backend/app/db/session.py
@@ -1,20 +1,37 @@
 from sqlalchemy import create_engine
-from sqlalchemy.orm import sessionmaker,declarative_base
-
+from sqlalchemy.orm import sessionmaker, declarative_base, Session
 from app.core import config
 
-engine = create_engine(
-    config.SQLALCHEMY_DATABASE_URI,
-)
-SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
 
 Base = declarative_base()
 
+# engine = create_engine(
+#     config.SQLALCHEMY_DATABASE_URI,
+# )
+# SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
 
-# Dependency
-def get_db():
-    db = SessionLocal()
+class Database:
+    def __init__(self, database_url: str):
+        self.database_url = database_url
+        self.engine = create_engine(self.database_url)
+        self.SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=self.engine)
+        self.Base = declarative_base()
+
+    def get_db(self):
+        db =self.SessionLocal()
+        return db
+
+tenantdb = Database(config.SQLALCHEMY_DATABASE_URI)
+
+
+def get_tenant_db():
+    db = tenantdb.get_db()
     try:
-        yield db
+        yield db  
     finally:
-        db.close()
+        db.close() 
+
+def get_user_db(database_url: str):
+    database = Database(database_url)
+    db = database.get_db()
+    return db
diff --git a/backend/app/main.py b/backend/app/main.py
index 0f4c089..b718962 100644
--- a/backend/app/main.py
+++ b/backend/app/main.py
@@ -8,7 +8,7 @@ from app.api.api_v1.routers.users import users_router
 from app.api.api_v1.routers.auth import auth_router
 from app.api.api_v1.routers.platform import platform_router
 from app.core import config
-from app.db import Base,engine
+#from app.db import Base,engine
 from app.core.auth import get_current_active_user
 from app.core.celery_app import celery_app
 from app import tasks
@@ -22,7 +22,7 @@ import asyncio
 from contextlib import asynccontextmanager
 
 
-Base.metadata.create_all(bind=engine) 
+#Base.metadata.create_all(bind=engine) 
 
 @asynccontextmanager
 async def lifespan(app: FastAPI):
diff --git a/backend/app/tests/conftest.py b/backend/app/tests/conftest.py
index a989443..d7bb3d4 100644
--- a/backend/app/tests/conftest.py
+++ b/backend/app/tests/conftest.py
@@ -5,7 +5,7 @@ from fastapi.testclient import TestClient
 import typing as t
 
 from app.core import config, security
-from app.db.session import Base, get_db
+from app.core.dbmanager import get_db
 from app.db import models,schemas
 from app.main import app
 
@@ -42,9 +42,12 @@ def test_client(test_db):
     with TestClient(app) as test_client:
         yield test_client
 
+@pytest.fixture(scope="session")
+def test_tenant_id():
+    return "1"
 
 @pytest.fixture(scope="session")
-def test_user(test_db):
+def test_user(test_db,test_tenant_id):
     password ="test"
     user = models.User(
         email = "test@test.com",
@@ -52,7 +55,8 @@ def test_user(test_db):
         last_name = "abc",
         hashed_password = security.get_password_hash(password),
         is_active = True,
-        is_superuser = False
+        is_superuser = False,
+        tenantid = test_tenant_id
     )
     test_db.add(user)
     test_db.commit()
@@ -66,26 +70,28 @@ def password():
     return "password"
 
 @pytest.fixture(scope="session")
-def user(password):
+def user(password,test_tenant_id):
     user = models.User(
         email = "user@test.com",
         first_name = "user",
         last_name = "abc",
         hashed_password = security.get_password_hash(password),
         is_active = True,
-        is_superuser = False
+        is_superuser = False,
+        tenantid = test_tenant_id
     )
     return user
 
 @pytest.fixture(scope="session")
-def admin(password):
+def admin(password,test_tenant_id):
     user = models.User(
         email = "admin@test.com",
         first_name = "admin",
         last_name = "abc",
         hashed_password = security.get_password_hash(password),
         is_active = True,
-        is_superuser = True
+        is_superuser = True,
+        tenantid =test_tenant_id
     )
     return user