CS Interview Preparation - Database Edition: Insights Directly from Channel Talk Interviewers

🤬 Database interviews—I definitely know all the content, so why can't I get the words out?!

I'm Jayon, currently working as a backend engineer and interviewer at Channel Talk, after completing the Woowa Course and working as a backend engineer at several companies. I wasn't someone who was good at interviews from the start. In fact, I ranked near the bottom in the Woowa Course mock interviews and even had to have a separate meeting with the CEO.

Transaction isolation levels? I knew them. Index operating principles? Of course, I had them organized. But everything changed once I sat down in the interview room.

"Please explain the types of transaction isolation levels." Up to this point, it was fine. I recited everything just as I had prepared. But the moment the interviewer pointed to one of my answers and asked, "Then how is Phantom Read resolved in REPEATABLE READ?" my mind went completely blank. I had definitely seen it somewhere. I had even summarized it. But in that moment, sitting right there, I just didn't know what to say.

Searching it on my phone after the interview and thinking, "Ah, it was this..." That feeling of emptiness... I'm sure many of you can relate.

From that point on, I started recording and reviewing my interviews. I created "incorrect answer notes" and compared my previous answers with my current ones for the same questions. As I accumulated over hundreds of questions and answers, patterns began to emerge. I started to see which answers convinced the interviewers and which ones invited unnecessary follow-up questions.

It was only after going through this trial and error hundreds of times that I realized: knowing the theory and speaking in an interview are completely different skills. That's why I decided to create a lecture focused solely on "how to answer the questions."

✨ 4 Key Points I Focused on While Creating the Course

👍 This is recommended for the following people!

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✔ Notes

1. The class proceeds on the assumption that you have at least a basic understanding of database fundamentals. The effectiveness of the lecture will be maximized if you have been exposed to concepts such as transactions and indexes at least once.

2. If you happen to encounter any parts you don't understand while studying, please ask immediately by using the Q&A board😊

   
   

🚨 Be sure to check who the person providing the education is!

If you meet the wrong doctor, you may die because you cannot cure your illness at that moment. However, death ends with the pain of that moment. But if you meet the wrong teacher and receive a poor education, you will suffer for the rest of your life.

Due to poor education, you may end up at a company you didn't want, receive a smaller salary than expected, and suffer for the rest of your life as a result. Not only that, but the poor education you received can even be passed down to your children.

I believe that education can truly change a person's life for the better, but on the other hand, it can also completely ruin a person's life. That is why I believe education carries such a heavy responsibility.

Therefore, please check who the educator is, what kind of person they are, and what path they have taken, and make a careful decision.

👋 Hello!
I'm finally introducing myself ( ⸝⸝•ᴗ•⸝⸝ )੭⁾⁾

Hello!

I am Jayon, a 5th-year developer working as a backend engineer at Channel Talk.

I completed the Woowa Course 3rd Backend program and started my career at a small SI company. My salary was at the minimum level. To escape that situation, I poured a tremendous amount of time into preparing for coding tests and interviews. As a result, after passing through Chai Corporation (PortOne), I am currently earning several times my initial salary while managing Channel Talk's core system, which handles billions of records.

I felt it while going through this process: it is truly difficult to find the right direction when preparing for a job alone. That is why I have been active as a backend mentor at F-Lab, JSCODE, and Fast Campus, and also served as a reviewer for the 5th Woowa Tech Course. Through mentoring, I have produced successful candidates for companies like Naver, Kakao, Line, Coupang, Baemin, Danggeun, Toss, unicorn startups, and major corporations, and the know-how accumulated during that process is fully contained in this lecture.

Just as I received a lot of help when I was going through difficult times, I wanted to become someone who could help many others as well. I felt most proud and happy when the value I created through development had a positive impact on other people.

I also run a technical blog steady-coding, so if you're curious about what kind of developer I am, please feel free to visit!

Thank you!

🚌 If you're feeling overwhelmed about which order to take the courses in?

Please refer to '[2026] Essential Curriculum for Becoming a Backend Developer (IT Service Companies)'!!

🐶 Get course discounts with the roadmap

➡ CS interview preparation tips directly from a Channel Talk interviewer

(https://inf.run/8VEbS)