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@NewQuietBear2 ай бұрын
Interessant, ik heb ORM's gebruikt bijvoorbeeld en alhoewel ik nog niet bekend was met de onderliggende patronen, herken ik een hoop terug doordat ik deze packages ooit heb gebruikt.
@iamkaransethi5 ай бұрын
I liked your calm and composed style of explaining a complex topic.Well done, your 3rd example made the most sense to me in terms of rollbacks scenario - IaC setup seems like a good place to use this design pattern. Thanks, Arjan!
@ArjanCodes5 ай бұрын
Glad it was helpful!
@inhahe5 ай бұрын
You asked about other ideas for use of the unit of work..one thing that came to mind was installing programs. All program installations seem to be able to roll back everything if the installation fails for some reason.
@spanomatic5 ай бұрын
Unit of work is used in Guaranteed messaging between systems and applications (messaging middleware). send message and ack that sort of thing. Redis also has batch functions to perform several ops at once.
@kaosce5 ай бұрын
But in the case of unit of work between systems, you would need a separate system dedicated to centralizing these operations. Would it still be a good idea?
@spanomatic5 ай бұрын
@@kaosce In a best case I would think so too. But I have see it both ways with the middle ware running on the same server as the app, but it is a separate app for sure.
@avazart6145 ай бұрын
Session has method/contextmanager "begin" for control transaction. SQLAlchemy has special mixin for using as dataclass "MappedAsDataclass" (for __str__/__repr__)
@Lexaire5 ай бұрын
SQLAlchemy is so powerful it's almost too powerful. Learning to use everything SQLAlchemy has is like a full time job in itself.
@uruzrune72165 ай бұрын
Would you consider doing a Saga Pattern video? Also, can you demonstrate using Saga and Unit of Work together to roll back a failed Saga?
@hcubill5 ай бұрын
Excellent video! I had never heard of this, gives me good ideas how to change our code!
@ArjanCodes5 ай бұрын
Glad it was helpful!
@aashayamballi5 ай бұрын
can you please cover django concepts as well?
@edgeeffect5 ай бұрын
My favourite ORM for PHP (sorry) uses UOW... so much nicer than those other Active Record ORMs. I did an extension that logged database changes to.... the database by scanning and extending the UOW on a commit... I had Python friends (I was doing JS) at my old job who used SQL Alchemy and I was always curious as to what was inside... now I really want to try it. UOW is my favorite underrated pattern - "boo!" to Active Record.
@jamesclarke72595 ай бұрын
As always thanks, could you maybe do one on django?
@klmcwhirter5 ай бұрын
Please take a look at the echo=True option to the create_engine function. This will ask sqlalchemy to output db interaction info including the sql statements being executed and more ... Another great video. The UnitOfWork and Repository patterns are critical to building resilient, reliable persistence layers - and not just with db, but also filesystem, web service APIs, etc. !
@obsidiansiriusblackheart5 ай бұрын
I used to work for a PoS company and I accidentally implemented Unit of Work pattern without knowing it existed :) mine was a bit janky though, a dict of bools that was tracked between methods to know from which step we had to rollback
@hubstrangers34505 ай бұрын
Thank you....would be ideal scenario for embedded DBs (DuckDB, targeting scientific workloads, with specific pythonic libraries)
@StarLord19965 ай бұрын
Do I need a different implementation of this pattern for each use-case in my domain?
@BuFu1O15 ай бұрын
Do a coderoast of the nanogpt repo of Andrej Karpathy
@lucianop.39225 ай бұрын
This looks extremely similar to using an event queue. Throughout the lifetime of your program, you add events to a queue, and you delay their execution to a point where it is convenient (for any reason depending on context, in a game you might want to apply some filtering to change the order of events and process some before others), so it gives you full control on the order of execution. But, it can also help you to see which events failed, and then do the appropriate rollback. EDIT: On second thought, it is an event queue, but used in a different context with (potentially) different intentions.
@kennyostrom30985 ай бұрын
"Command" comes closest in the classic gang of four design patterns, and it mentions having a rollback queue.
@TheEvertw5 ай бұрын
Any design pattern is a combination of 4 (sometimes more) classes doing something together. The description of the context makes a design pattern useful. Personally, I consider the UoW pattern a merge of the Command and the Decorator patterns. Any queuing feature is not part of the actual pattern, though real implementation will usually have queuing as well. Like most real implementations of the Command Pattern also have queuing, but it is not part of the pattern itself.
@nimmneun5 ай бұрын
Yup, we use Workers in combo with UOWProviders that are responsible for orchestration /execution/rescheduling and gathering any required data to create a UOW.