<type 'exceptions.ValueError'> insecure string pickle

[karthikeyan p]

hi . 

i am running web2py app in pythonanywhere  - its version is Version 2.17.1-stable+timestamp.2018.08.06.01.02.56

i pull the app via git to my local machine which has Version 2.18.5-stable+timestamp.2019.04.08.04.22.03

when i tried to open the app  , i got this error 

<type 'exceptions.ValueError'> insecure string pickle

after that i saw some solution in google groups ;

mostly i found this

https://groups.google.com/forum/#!topic/web2py/P-dU23VOO3o

1. (Backup and) delele database/*.table files

2. Into db=DAL(..) command add db=DAL(..., fake_migrate_all=True), then run once: app/appadmin/ or some other page

3. Remove fake_migrate_all=..

but the thing is  , i want :

1. data base from pythonanywhere to my local machine to process 
2. any devOps idea for implementing web2py for easy long-term efficient use like docker ?
3. if i use postgresql , this error will occur due to DAL ?