Python

We understood that we do not have an index, so we created an index. In what situations might this index not work?

What architecture is needed for an internet store support agent if all the infrastructure (chat, backend) is already ready?

Have you used decorators in your work? For what purposes?

Mutable and immutable data types in Python. List, tuple, dictionary, int, set, string, bool — which are mutable and which are not?

I have a custom handwritten class. I want it to be a dictionary key. What should I do?

How are Python variables stored in RAM?

Is it possible to add both synchronous (__enter__, __exit__) and asynchronous (__aenter__, __aexit__) context manager methods in one class?

We performed EXPLAIN ANALYZE on a query. What could be the problems with the query? How do you approach analysis?

How does asynchrony work at the event loop level — why doesn't the thread wait for the operation to complete?

What is fine-tuning, when is it needed, can it be done independently, and with what tools?

We have a dual-lever database — master and replica. We made a transaction, it went through, data appeared on the master. The power went out on the replica, the server crashed, data did not arrive there. What will happen when the server is restored?

How does Kafka outperform Redis Pub/Sub?

What is the difference between Kafka and RabbitMQ?

A little about OOP. What is the difference (between some OOP concepts)?

What types of prompts exist?

Was this a high-load service?

Can there be two primary keys on one table in PostgreSQL?

What is the difference between EXPLAIN and EXPLAIN ANALYZE in PostgreSQL?

Are there situations where the complexity of operations with a dictionary will be worse than O(1)?

How does the model technically 'call' tools if it simply predicts text?