Hello my Friends;
I am trying to migrate an odoo database from the version 11 to the version12.
So, i am using OpenUpgrade.
But, the problem is that when i try to launch the process i got this error:
2019-07-26 13:46:36,059 9902 INFO ? odoo: Odoo version 12.0 
2019-07-26 13:46:36,060 9902 INFO ? odoo: Using configuration file at /etc/odoo12.conf 
2019-07-26 13:46:36,060 9902 INFO ? odoo: addons paths: ['/opt/OpenUpgrade/addons', '/opt/OpenUpgrade/odoo/addons'] 
2019-07-26 13:46:36,060 9902 INFO ? odoo: database: odoo12@default:default 
2019-07-26 13:46:36,109 9902 CRITICAL ? odoo.modules.module: Couldn't load module base 
2019-07-26 13:46:36,109 9902 CRITICAL ? odoo.modules.module: module 'odoo.tools' has no attribute 'yaml_import' 
2019-07-26 13:46:36,110 9902 ERROR ? odoo.service.server: Failed to load server-wide module `base`. 
Traceback (most recent call last):
  File "/opt/OpenUpgrade/odoo/service/server.py", line 1063, in load_server_wide_modules
    odoo.modules.module.load_openerp_module(m)
  File "/opt/OpenUpgrade/odoo/modules/module.py", line 368, in load_openerp_module
    __import__('odoo.addons.' + module_name)
  File "<frozen importlib._bootstrap>", line 971, in _find_and_load
  File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 656, in _load_unlocked
  File "<frozen importlib._bootstrap>", line 626, in _load_backward_compatible
  File "/opt/OpenUpgrade/odoo/modules/module.py", line 82, in load_module
    exec(open(modfile, 'rb').read(), new_mod.__dict__)
  File "<string>", line 5, in <module>
  File "/opt/OpenUpgrade/odoo/addons/base/models/__init__.py", line 7, in <module>
    from . import ir_model
  File "/opt/OpenUpgrade/odoo/addons/base/models/ir_model.py", line 17, in <module>
    from openupgradelib import openupgrade
  File "/usr/local/lib/python3.6/dist-packages/openupgradelib/openupgrade.py", line 84, in <module>
    yaml_import = tools.yaml_import
AttributeError: module 'odoo.tools' has no attribute 'yaml_import'
2019-07-26 13:46:36,138 9902 INFO database-demo odoo.modules.loading: loading 1 modules... 
2019-07-26 13:46:36,147 9902 ERROR database-demo odoo.modules.migration: module base: Each pre-migration file must have a "migrate(cr, installed_version)" function 
2019-07-26 13:46:36,150 9902 INFO database-demo odoo.modules.registry: module base: creating or updating database tables 
2019-07-26 13:46:36,151 9902 ERROR database-demo odoo.sql_db: bad query: b"\n        SELECT c.relname\n          FROM pg_class c\n          JOIN pg_namespace n ON (n.oid = c.relnamespace)\n         WHERE c.relname IN ()\n           AND c.relkind IN ('r', 'v', 'm')\n           AND n.nspname = 'public'\n    "
ERROR: syntax error at or near ")"
LINE 5:          WHERE c.relname IN ()
                                     ^
Need your help please.
Thanks a lot in advance.
Best regards.
 
                        
Please help this issue