Golang

What is the main programming language and what other languages do you know, including non-commercial experience?

What is the current algorithmic search complexity?

Tell about a project in Roistat — what is the project and why did you leave?

Condition There are 3 entities - user, chat, message • User has a name and registration date • Chat has a name and creation date • Message has text, author, and creation date • A user can be in multiple chats simultaneously • A message must belong to a chat, and cannot belong to more than one chat at the same time • Describe the domain in the form of tables

We need to restart a service (update/feature) — what impact will this have on asynchronous processes sending data to analytics?

You used serial id everywhere. What does it mean?

Where do you see yourself in the future — as an expert, Tech Lead, or architect?

How to understand that a query will use this index? Do you know any SQL construct to check this?

How do indexes affect reading and writing — do they speed up or slow down?

What is the difference between text and varchar?

If we reach the capacity of our in-memory solution, what could you suggest for memory cleanup?

Here you also mention imbalance with another generation method. Can you tell what it is about?

Suppose RPS (Black Friday) suddenly increased sharply, and the analytics service cannot cope — what can be done?

Can you explain what a collision is in the context of this task? And can there be collisions in your code?

When are deffered functions executed?

There are 3 entities - user, chat, message • The user has a name and registration date • The chat has a name and creation date • The message has text, author, and creation date • A user can be in multiple chats simultaneously • A message must belong to a chat, and a message cannot belong to more than 1 chat at the same time • Describe the domain in the form of tables -- Select all chats of the user Vasya in the format (chat_id, chat_name)

Why can't we add an index to each field in advance just in case?