How a front-end developer passed the PostgresPro certification

Let me make a reservation, the title is clickbait, and for about the last 2 years of my work within my company I am considered a full-stack developer, but still my base is frontend and I do not have any special education.

I want to share how I prepared for certification. What kind of questions were there. How difficult it was for a person who knew nothing about DBMS and used the DB at the level of elementary queries, as well as a small part of my thoughts on the topic of how much this is generally necessary.

The problem itself

My technical director had a great idea – to create a “crisis” team. In general terms, this is a team of developers, each member of which can close a wide range of development tasks in the stack used in our company – k8s, docker, vue, golang. Can communicate with the customer, collect requirements, and then turn them into something like analytics. And most importantly, in a short time, possibly with overtime, solve critical problems, but in quiet times will have the opportunity to take a rest. To get into it, you need to pass a series of tests, the first of which was the presence of a PostgresPro DBA-1 certificate, and in a very short time of about 1.5 months.

Stages of adoption

At first I wanted to just drop out right away, it all seemed like a huge problem to me, starting with logistics (I don't live in Moscow) and ending with the certification procedure itself. In the end I pulled myself together and started training.

What awaits you

Event format:
50 multiple choice questions, as well as questions where you need to type the answer, the entire task is given 75 minutes. You can use the course materials and documentation.

I took the DBA-1 (13) program, not long ago PostgresPro updated the training materials and the questions themselves, now it is DBA-1 (16), and they made a review topic with which I had the hardest time – “Access control“.

During the certification itself, I chose the following tactic – I'll skip questions that I don't know the answer to, answer the easy ones, and then come back, and scrolling through the 20th question in a row, I began to panic. A meme immediately popped into my head, and I think it accurately reflects what awaits you.

1 attempt

I prepared quite diligently, for a month, I devoted 1.5-2 hours to watching lectures, solving the problems attached to them, and also additionally came up with some problems and tried to solve them.

I arrived in Moscow, answered the questions, and in anticipation of victory, waited for 2:00 PM the next day (the results are announced the next day). I receive the result.

Let me remind you, the passing score is 75%. At this point, my hands dropped and I gave up on this idea. As a result, out of 10 candidates, only 1 employee made it onto the team.

2nd attempt

After 2 months, I finally decided to try my hand again.
Having already understood my weak points, I began preparing, placing greater emphasis on these topics.

I came to Moscow again. Already more confident in my abilities, I started reading the questions. I expected to see questions not much different from those from the first exam, but no way, they changed a lot, their form and content became even more complex, panic covered me again. I later learned from the organizers that the formats change for subsequent exams, then a direct quote “you have already worked through the questions from the first exam, of course they will not be repeated” and “don't be upset, according to statistics, DBA-1 passes on the 3rd try”. Confident of failure, I flew home.

The next day the results came.

How would I prepare now?

You can't hand it over “for free”, you have to accept it.

I would start preparing 2-3 months before certification, and watch one lecture per day, and pay more attention to practical tasks. They only consider the so-called happy path, consider edge cases, break and fix something.

Don't ignore the links to documentation in the materials, and the links within them, because I have come across questions that were answered in the documentation, not in the materials. It's not so much important for you to memorize everything, but rather you need to know and quickly be able to find information in the documentation.

Don't google, don't use GPT and other usual sources, look for answers to any questions only in the PostgresPro documentation.

You can open the documentation in 2 ways.

We immediately discard the first option; when viewing a PDF in a browser, in fact, only the displayed pages are rendered; when trying to find something through a standard text search, nothing will come of it.

It is better to download the archive immediately, and the search will work adequately. I did the same thing during certification, there was no explicit prohibition.

You will be told a hundred times to read the questions carefully, this is really true. When you first read the question, a bunch of different “and if so”, “and if such a setting is enabled”, “and if such a parameter is set” appear in your head, forget about any “ifs”, choose the simplest path, no need to think.

Many questions are tricky, the main thing is not to get caught. For example, in the question a huge select was made from pg_class + some join from the pg_database table, etc. The result of this query was displayed, and the question itself sounded like this. With which DBs was the cluster initialized? If you have already watched the course, or know postgres, then you understand that this select was needed only to confuse you.

Is it necessary?

Whether he needs a certificate or not, everyone must decide for themselves. I basically needed it to get into the team, someone needs it because their employer asks for it when applying for a job. I don't see much point in taking it just for the sake of having it. If you are really motivated to learn something, I think you will study everything yourself in good faith.

For myself, I gained a lot of benefit, in general I think that this certification is not about Postgres as a tool, but rather about the system. I learned a lot of architectural decisions that were made in the DBMS, which I had no idea about, how transactionality is provided, what WAL logs are, how data is stored, how the system interacts with the OS, etc.

I hope my article will help someone get the desired certificate.