Hello, my name is Yonan Tang and I am a CDA Level I holder. I'm glad to share my preparation experience with you here.

I am a senior student majoring in Data Science and Big Data Technology, studying in the School of Statistics and Mathematics at Zhongnan University of Economics and Law.

After I failed the exam in the first semester of my senior year, I plan to find a job related to data analysis. I think if I can get the CDA certificate, I can be competitive in the job hunting process.

How I prepared for the exam
I had a lot of free time every day, so I studied for about two hours a day, watched the video course, and started to do mock questions after I finished all the courses. It took about a month to review.

I watched the video course at 2x speed, and quickly went through it, repeating the places I didn't understand a few times to take a closer look.

When learning the database part, follow the course and do it yourself, you will be more familiar with the SQL language, which will help us remember. When I finished listening to the whole course and doing the mock questions, I did it unit by unit and added the knowledge points to the lesson after staring at them, and then went through the whole unit again.

In short, to improve self-awareness, the course did not understand the knowledge points to take the initiative to look up online to understand the record.

I feel that the difficult part of the preparation is the sixth chapter, about the e-commerce business is the first time I contact, many of the terminology I have not heard, like the snowflake model constellation model these, are very difficult to understand things. So for this knowledge I will look up some extracurricular materials and actively go online to fill in the gaps in my knowledge.

Next is the knowledge of statistics, although I am a student of statistics, but this section is still very difficult, the formula and distribution have to understand, but also to know the various tests to be used in what situation, in short, is to read more examples, think clearly about the difference between them.

My recommended books
Statistics and probability theory part I recommend Jia Junping's "Statistics", which is very clear and easy to understand the various distributions, interval distributions, hypothesis testing, etc., which is very helpful for the exam.

I didn't read any additional books for the other sections in Level Ⅰ, just follow the videos in the course on the official website and study carefully.

In my opinion, getting the CDA Level Ⅰ certification is a confirmation of my current ability in all aspects of data. I hope I can go farther and farther on the road of data analysis, learn more knowledge and skills, improve myself and realize my self-worth.