There was an issue while migrating the DocType: Purchase Order, after bench update --reset

I execute bench update --reset and this error consist on bench migrate

There was an issue while migrating the DocType: Purchase Order

Traceback (most recent call last):
File “/usr/lib/python3.5/runpy.py”, line 184, in _run_module_as_main
main”, mod_spec)
File “/usr/lib/python3.5/runpy.py”, line 85, in _run_code
exec(code, run_globals)
File “/home/frappe/frappe-bench/apps/frappe/frappe/utils/bench_helper.py”, line 97, in
main()
File “/home/frappe/frappe-bench/apps/frappe/frappe/utils/bench_helper.py”, line 18, in main
click.Group(commands=commands)(prog_name=‘bench’)
File “/home/frappe/frappe-bench/env/lib/python3.5/site-packages/click/core.py”, line 722, in call
return self.main(*args, **kwargs)
File “/home/frappe/frappe-bench/env/lib/python3.5/site-packages/click/core.py”, line 697, in main
rv = self.invoke(ctx)
File “/home/frappe/frappe-bench/env/lib/python3.5/site-packages/click/core.py”, line 1066, in invoke
return _process_result(sub_ctx.command.invoke(sub_ctx))
File “/home/frappe/frappe-bench/env/lib/python3.5/site-packages/click/core.py”, line 1066, in invoke
return _process_result(sub_ctx.command.invoke(sub_ctx))
File “/home/frappe/frappe-bench/env/lib/python3.5/site-packages/click/core.py”, line 895, in invoke
return ctx.invoke(self.callback, **ctx.params)
File “/home/frappe/frappe-bench/env/lib/python3.5/site-packages/click/core.py”, line 535, in invoke
return callback(*args, **kwargs)
File “/home/frappe/frappe-bench/env/lib/python3.5/site-packages/click/decorators.py”, line 17, in new_func
return f(get_current_context(), *args, **kwargs)
File “/home/frappe/frappe-bench/apps/frappe/frappe/commands/init.py”, line 25, in _func
ret = f(frappe._dict(ctx.obj), *args, **kwargs)
File “/home/frappe/frappe-bench/apps/frappe/frappe/commands/site.py”, line 223, in migrate
migrate(context.verbose, rebuild_website=rebuild_website)
File “/home/frappe/frappe-bench/apps/frappe/frappe/migrate.py”, line 41, in migrate
frappe.model.sync.sync_all(verbose=verbose)
File “/home/frappe/frappe-bench/apps/frappe/frappe/model/sync.py”, line 19, in sync_all
sync_for(app, force, verbose=verbose, reset_permissions=reset_permissions)
File “/home/frappe/frappe-bench/apps/frappe/frappe/model/sync.py”, line 56, in sync_for
reset_permissions=reset_permissions, for_sync=True)
File “/home/frappe/frappe-bench/apps/frappe/frappe/modules/import_file.py”, line 65, in import_file_by_path
ignore_version=ignore_version, reset_permissions=reset_permissions)
File “/home/frappe/frappe-bench/apps/frappe/frappe/modules/import_file.py”, line 133, in import_doc
doc.insert()
File “/home/frappe/frappe-bench/apps/frappe/frappe/model/document.py”, line 248, in insert
self.run_post_save_methods()
File “/home/frappe/frappe-bench/apps/frappe/frappe/model/document.py”, line 915, in run_post_save_methods
self.run_method(“on_update”)
File “/home/frappe/frappe-bench/apps/frappe/frappe/model/document.py”, line 780, in run_method
out = Document.hook(fn)(self, *args, **kwargs)
File “/home/frappe/frappe-bench/apps/frappe/frappe/model/document.py”, line 1058, in composer
return composed(self, method, *args, **kwargs)
File “/home/frappe/frappe-bench/apps/frappe/frappe/model/document.py”, line 1041, in runner
add_to_return_value(self, fn(self, *args, **kwargs))
File “/home/frappe/frappe-bench/apps/frappe/frappe/model/document.py”, line 774, in
fn = lambda self, *args, **kwargs: getattr(self, method)(*args, **kwargs)
File “/home/frappe/frappe-bench/apps/frappe/frappe/core/doctype/doctype/doctype.py”, line 258, in on_update
raise e
File “/home/frappe/frappe-bench/apps/frappe/frappe/core/doctype/doctype/doctype.py”, line 255, in on_update
frappe.db.updatedb(self.name, self)
File “/home/frappe/frappe-bench/apps/frappe/frappe/database/mariadb/database.py”, line 278, in updatedb
db_table.sync()
File “/home/frappe/frappe-bench/apps/frappe/frappe/database/schema.py”, line 36, in sync
self.alter()
File “/home/frappe/frappe-bench/apps/frappe/frappe/database/mariadb/schema.py”, line 86, in alter
raise e
File “/home/frappe/frappe-bench/apps/frappe/frappe/database/mariadb/schema.py”, line 75, in alter
frappe.db.sql(query)
File “/home/frappe/frappe-bench/apps/frappe/frappe/database/database.py”, line 165, in sql
self._cursor.execute(query)
File “/home/frappe/frappe-bench/env/lib/python3.5/site-packages/pymysql/cursors.py”, line 170, in execute
result = self._query(query)
File “/home/frappe/frappe-bench/env/lib/python3.5/site-packages/pymysql/cursors.py”, line 328, in _query
conn.query(q)
File “/home/frappe/frappe-bench/env/lib/python3.5/site-packages/pymysql/connections.py”, line 516, in query
self._affected_rows = self._read_query_result(unbuffered=unbuffered)
File “/home/frappe/frappe-bench/env/lib/python3.5/site-packages/pymysql/connections.py”, line 727, in _read_query_result
result.read()
File “/home/frappe/frappe-bench/env/lib/python3.5/site-packages/pymysql/connections.py”, line 1066, in read
first_packet = self.connection._read_packet()
File “/home/frappe/frappe-bench/env/lib/python3.5/site-packages/pymysql/connections.py”, line 683, in _read_packet
packet.check_error()
File “/home/frappe/frappe-bench/env/lib/python3.5/site-packages/pymysql/protocol.py”, line 220, in check_error
err.raise_mysql_exception(self._data)
File “/home/frappe/frappe-bench/env/lib/python3.5/site-packages/pymysql/err.py”, line 109, in raise_mysql_exception
raise errorclass(errno, errval)
pymysql.err.InternalError: (1138, ‘Invalid use of NULL value’)

Any idea on this?

@rmehta any idea? I have opened an issue on github There was an issue while migrating the DocType: Purchase Order / Invalid use of NULL value · Issue #16170 · frappe/erpnext · GitHub

You are on 3.5 when 3.6 is supported?