flask_SQLAlchemy中的TIMESTAMPDIFF的替代方法

Question

我正在移植旧代码，MySQL-> flask_SQLAlchemy。

下面是更新代码的摘要。

from flask_sqlalchemy import SQLAlchemy                                                                                                                                                        
from myapp import APP                                                                                                                                                                          
from myapp.models.nodes import Host                                                                                                                                                            


DB = SQLAlchemy(APP)  
# config is taken care here                                                                                                                                                                         

APP.app_context().push()                                                                                                                                                                       
with APP.app_context():                                                                                                                                                                        
    DB.init_app(APP)     

Hostname_var = "some hostname"
session_query = Host.query.filter_by(hostname=hostname_var).first()
...

我想找到下面代码的替代方法，但是找不到

c.execute("select sessions.id,sessions.delivered_at from sessions,users where TIMESTAMPDIFF(HOUR, now(),sessions.delivered_at) < %d " % (state,j,state_timeout))

感谢您的帮助，谢谢。