Frequently Asked Questions¶
ORM or not ORM?¶
GINO does perform the Object-Relational Mapping work under the Data Mapper Pattern, but it is just not a traditional ORM. The Objects in GINO are completely stateless from database - they are pure plain Python objects in memory. Changing their attribute values does not make them “dirty” - or in a different way of thinking they are always “dirty”. Any access to database must be explicitly executed. Using GINO is more like making up SQL clauses with Models and Objects, executing them to make changes in database, or loading data from database and wrapping the results with Objects again. Objects are just row data containers, you are still dealing with SQL which is represented by Models and SQLAlchemy core grammars. Besides GINO can be used in a completely non-ORM way.
How to join?¶
GINO invented none about making up queries, everything for that is inherited from SQLAlchemy. Therefore you just need to know how to write join in SQLAlchemy. Especially, Ádám made some amazing upgrades in GINO #113 to make join easier, so that you can use model classes directly as if they are tables in joining:
results = await User.join(Book).select().gino.all()
How to connect to database through SSL?¶
engine = await gino.create_engine(..., ssl=True)
Transaction cannot rollback changes?¶
As for now, make sure aiocontextvars is installed in order to use contextual transactions like this:
async with db.transaction(): await MyModel.create(name='xxx')
Or else if you’d prefer not to install an additional dependency, you’ll have to modify the code to explicitly use the correct connection:
async with db.transaction() as tx: await MyModel.create(name='xxx', bind=tx.connection)
Since GINO 0.7.4,
aiocontextvars became a required dependency.