@alexeymalashkevich I just need to get the user to each server when I select a server.

I don't get it. How to setup this simple relationship. 1:n between users->servers and 1:1 between server and user. current code: https://pastebin.com/raw/jAxA16b6

There is no other offline tool for pony, I feel so sad, cause I live in a place which is internet being scarce

Currently we are not working on an offline editor But the new version of the online tool is 99% ready @luckydonald, we count on you as a beta tester ;)

Just send me how to :D

to call db.generate_mapping twice?

I don't get the relationship running, can someone please take a look into: https://pastebin.com/raw/kTEEX4SG

> i would make any sense if i sort of edit dynamically the database structure > to call db.generate_mapping twice? It is not possible (at least for now) to call generate_mapping twice, but you can generate entities inside a function and call that function several times with a different db objects def define_entities(db): class Person(db.Entity): name = Required(str) db1 = Database() define_entities(db1) db2 = Database() define_entities(db2)

quick question here: if I change the entity structure in my app and restart it, can I get Pony to update the current tables, or do I have to drop the tables and start over?

I'm still in dev phase so it's not too much of an issue

What is the best way to change out the primary key of a database? Probably making another database and export/import? I don't wanna do it manually, would it work to specify two different versions of the database and copy the data in python?

primary key of a table?

looks like len(Entity.select()) works, is this a fine way of doing it?

any of this: select(count() for x in MyObject).get() get(count() for x in MyObject) MyObject.select().count() also possible: select(count(x) for x in MyObject).get() get(count(x) for x in MyObject)

https://editor.ponyorm.com/user/luckydonald/Tags The `Sticker` table has a `file_id` column, which is PK. Problem is, Telegram recent changed the way the file IDs are calculated. So I am required to change 'em all. Problem is many tables are referring it. I think the best would to replace it with a Auto increment PK, in case there are future changes.

I think this case is too hard for migrations, because change of primary key is a very seldom operation and requires complex cascade actions. I suggest you to have two different files with definition of models, connect to both databases and copy objects from one database to another

looks like len(Entity.select()) works, is this a fine way of doing it?

Regarding counting the number of objects, actually the shortest form is: orm.count(x for x in MyObject)

select count(*) from table1

In all databases

Instead of obj.to_dict(obj) you need to write just obj.to_dict()

How does Pony handle float/double?

Pony represents float/double database type as float type in Python (which actually has double precision). The type of a database column which Pony creates is DOUBLE PRECISION. You can specify sql_type='real' if you want to create a column with a single precision

Well... you asked about get, and select is entirely different story. Pony should translate select generator code to SQL, and cannot translate your function, because it doesn't know what equivalent SQL should be. I don't know it too :) Also, the function that you wrote expects keyword arguments, not positional ones as you use inside the query. 1) I suggest you to write selects explicitly: games = select(g for g in Game if (g.name == name or name is None) and (g.version == version or version is None)) 2) You can also build query incrementally: query = select(g for g in Game) if name is not None: query = query.filter(lambda g: g.name == name) if version is not None: query = query.filter(lambda g: g.version == version) 3) Probably even something like that should work: def ignore_none(query, **kwargs): for key, value in kwargs.items(): if value is not None: query = query.filter(lambda x: getattr(x, key) == value) return query query = select(g for g in Game) query = ignore_none(query, name='X', version='Y') I didn't test it. Theoretically it should work, but there is an open issue 223, which describes a bug with getattr which is not fixed yet. You may follow approach (2) for safety

page_size = 1000 page_num = 1 while True: with db_session: objects = MyObject.select(). \ order_by(MyObject.id). \ page(page_num, page_size) process_objects(objects) if len(objects) < page_size: break page_num += 1