What are the interview topics for Python back-end engineers?

1. Recommend the best python book you have ever read?

2. talk about python decorator, iterator and yield?

3. Which queue in the standard library is thread-safe? Which one is not safe? Is the logging thread safe?

4.4. What are the suitable scenarios for Python? What should I do when I encounter a compute-intensive task?

5.python high concurrency solution? I want to hear distortion-> Tornado-> Gevent, let's say Golang and Erlang.

Two. operating system

It can be directly thought of as linux, after all, most people in the back end deal with linux.

1.What's the difference between TCP and UDP? What's with the tcp packet card and how to deal with it? Does udp have sticky packets?

2. what is 2.time_wait? What may be the reason for too many close_wait?

3. What is the difference between 3.EPOLL and SELECT? What is the difference between edge triggering and horizontal triggering?

Three. Storage; stock

Storage may include rdbms, nosql and cache. I take MySQL and Redis as examples.

Mysql correlation

1. Talk about mysql character set and sorting rules?

2.2. What's the difference between 2.2.varchar and char? Size limit? How many characters can varchar store in utf8 character set?

3.3. What's the difference between primary key and unique?

4. What's the use of foreign keys? Should foreign keys be used? Do foreign keys have to be indexed?

5.5. What's the difference between 5.5.myisam and innodb? What is the two-phase locking protocol of innodb?

6. What's the use of an index? What is the general principle? What should I pay attention to when designing an index?

Redis correlation

1. What scenario uses redis and why mysql is not suitable?

2. talk about redis's business? Using transactions to simulate atom+1 operation? Is there any other solution for atomic operation?

3.3. What happens when 3.3.redis is full of memory?

Four. security

Network security related

How is 1.sql injection produced and how to prevent it?

2. How to prevent 2.xss? Can xss be avoided after htmlescape?

3. What is 3.csrf? How did django guard against it?

Cryptography technology

1. What is block encryption? What are the encryption modes? What's the difference between ecb and cbc mode? Why do you need intravenous injection?

2. Simply put, the data analysis department of Longtu Game Operation Support Center recruits people; I think there is a problem, so what are you waiting for? Come and communicate with me.

Update: The discussion area is very lively. Some people say it's easy, others say it's difficult. In fact, I think it is only suitable for interviewing back-end engineers with 2~3 years working experience. I really didn't ask.

This is a difficult topic, but maybe you don't pay attention at ordinary times.

Here are some books to recommend to you.

Python reference manual will definitely take you to the next level.

Graphic password technology, the best choice for password input

The fifth edition of Mysql technology insider is a bit thick when reading the manual, so be patient. High-performance mysql is also highly recommended.

Effective tcp/ip programming

Why is the comment area so different? I think my personal experience is different. If I am engaged in the web, I will be weak in operating system and password technology, but if I am a system engineer or a game server, I will be obviously strong.

Postscript of intransitive verbs

Recently, I also interviewed many children's shoes and found that few of them can meet the requirements. Many hr say Python is the most difficult job to recruit, which makes sense to me. Is it really worth pondering?

I think part of the reason is the language Python. Many people can write Python, but few people can write it well. Most of them write Python as a script, lacking the idea of object-oriented and pattern-oriented. Think about Java, everyone is used to the separation of interface and implementation, and design patterns have been called in Java for many years, especially the ssh three frameworks, which is natural. Although there are some shortcomings, it is undoubtedly a great progress for enterprise Java development.

On the other hand, Python, especially generators, coprocessing and metaclasses, has injected great flexibility into Python. It is not difficult to write Python, but in fact Python has few advanced features, and if it is killed, it will be gone.

When you think Python has encountered a bottleneck, you might as well stop and think about it. Study design patterns, think about refactoring, understand domain-driven design and agile development, and then come back and read the code you wrote before. The higher the horizon, the more beautiful the code.

Of course, the improvement of thinking will not happen overnight. Patterns and principles often confuse you. If you struggle, you will think and find your own way. Of course, all roads lead to Rome

Storage technology such as database is an obstacle for R&D engineers. Take the relational database mysql as an example. You must know clearly what fields to choose, what type, byte size and restrictions. This thing is also easy to understand. Just think about it, such as assembly. To support operations such as intersection and merging, 1 byte can only store 8 categories. The data type is ready, and here is the index. What is mysql index type? Primary key, unique index, universal index. Index category, BTree index, hash index. Advantages and disadvantages of index, index search principle of mysql, join principle (mostly nested loop), and some special cases, such as mysql subquery is slow. In fact, R&D engineers are almost the same here. Of course, we can go further, such as separation of reading and writing, cluster management, and even some parameter tuning.