He is a genuinely helpful professor, who is always trying his best to help us learn and improve.

Professor is a very nice person, even there are quite a lot negative things you can say about this course by Rosario: 1. intensive course material, 2. hard test. I took this course with no awareness that it would be such intensive and hard almost like CS111: you have to read a lot about textbook chapter which is already an intensive workload(while eventhough it did not help a lot for the exam), each lecture slide is full of contents, really heavy, and the exam, especially final, can be said to be a nightmare if not well prepared, with even no one get an A- for the raw score.
That been said, these thing still don't negate the fact that Professor Rosario is a very nice person: he covered a lot in lecture because he did want us to learn a full image of database system, his giving hard exam seems not a real bad thing for me because it is an open book exam and indeed, after careful investment of effort you can get a really good grade for it. He tried to relieve us from too much consideration about letter grade, offering chances of enhancing the grade like replace the midterm grade with final one if you have done better in final, and even break his own originally designed grading rubric for homework to improve general grades for all. He really helped students a lot, especially in his office hour. He provide office hour almost every day during the week 10, and if you utilize them well, it will be really helpful.
He is tough and strict on rules in lecture and assignments, but it seems that he had his own ways to help students to learn without directly violate those rules. Pretty good man, if you see his last lecture slide with pages of them offering practical suggestions on both academy and industry.
Just a little post for RRR, whom I hated initially but respect at last, by all what he had done. Thanks professor:)

Took this class Spring2020 and it seemed like Rosario took a lot of feedback based on the previous negative reviews.

His tests were very fair and honestly on the easier side if you attended lecture and did the hw. He's very clear and has a good understanding of all the material so I made sure to attend all lectures.

He previously had large coding projects as a part of the class but this quarter instead chose to do smaller psets, which made the courseload very manageable.

He has good insights on the applications of databases due to his industry experience. Highly recommend you take this class with him

Rosario is an extremely arrogant cunt. He's an okay lecture and the first half of the class is alright but that's where the positives end. The second half of the class is extremely material dense where you are jumping from topics every lecture. Slides are very long. Rosario is also extremely unhelpful - he refuses any regrade requests and constantly berates and talks down on students. He's also just rly arrogant in general - he likes boasting about his vacations in Hawaii and mountain biking hobby and how expensive it is in his exam questions. Doesn't help that the midterms and final are difficult af. Don't take this class lmao.

I gotta say. Whatever criticisms Rosario previously got definitely wasn’t an issue this quarter.
I found the material (especially in the first half with SQL and Relational Algebra) really interesting and applicable. Same with the NoSQL stuff later.
While I didn’t find the more theoretical aspects as interesting, I still learned about its importance. I was a surprised at the different topics we covered.
My only complaint about the lectures — they’re too dense. Now it probably doesn’t help that we had to cancel a lecture due to the wildfires, but I found them to be extremely fast. I could barely keep up during the live lecture and I had to rewind the lecture about BCNF sooo many times that it probably took me double the time — and I consider myself a pretty fast note-taker. Other than that, he's a good speaker and gets the information out in a clear way as long as he isn't rushing.
As for the homeworks. I really enjoyed them. They tied in the lectures really well and they definitely helped with the exams.
As for the exams, I found it mostly fine, except for some ambiguity regarding some of the questions. The final was much harder and there were some problems that I wish he'd spend more time on lecturing it.
As for his helpfulnesss on piazza, there was this one time where he just wrote “Does your code resemble a proper python file” 3 different times. I feel like there was a better way to address that students’ questions but oh well…

unbelievable final exam

Leaving my first review on here as I feel strongly about helping prospective students decide if this specific class is right for them. TLDR: if grades don't matter to you, this is a class covering really relevant topics for industry and applications; if grades are a concern, I would not recommend this class due to (1) amount of content (2) the professor (3) the midterm and final

[1] Course Content: the class is split into SQL / RDBMS for the first 4 weeks and more technical concepts (indexing, architecture, NoSQL) for the latter half. He does a great job explaining the first half and teaching SQL, but the second half of the class is very confusing (subtopics are organized all over the place, 100 slides per lecture, no clear context). Amount of content is equivalent to CS 131 (a lot) and I would recommend taking CS 111 before taking this. Otherwise, all the actual TOPICS covered are very relevant and useful in applications and industry, which is why I would recommend taking it if you are purely interested in learning and not the grades.

[2] The midterm was difficult, with a class average of 68%. Rosario's tests are very detail oriented, there were MC questions asking you to recall a sentence he mentioned in lecture or a topic minimally explained in a single slide, so take detailed notes.

[3] The final, in my opinion, was just disrespectful. It was 3 hours between 6:30pm and 9:30pm, and he made the questions extraneous and incredibly convoluted. Explanations take up a page. It was very frustrating as half of the questions did not test understanding or knowledge (nor even through application), but rather it seemed he makes it unnecessarily hard for no reason. The questions derail you from actually applying what you learned. He also includes little notes or comments that waste your time and it overall felt very sarcastic, vain, and designed poorly. There obviously is a curve but this just demonstrates a lack of character and respect for students.

If you care about learning about databases and relevant topics surrounding that for your job, and you are not worried about the professor or final, then take it. Otherwise, if you have better options, I would highly recommend not wasting your time with Rosario!

One of my favorite courses I have taken at UCLA. Prof. Rosario really knows his stuff. I thought the assignments were extremely fair and the exams in lecture felt representative of what was displayed on exams. Some of the exam questions proved to be quite tricky but Prof. Rosario's expectations seem to reflect that students are learning and is willing to fairly represent the grades. Felt like I learned a lot about data management systems not only just hands on content but also some theory and internals for how data management systems work. Would highly recommend this class for all computer scientists.

This is such a useful class but Rosario is genuinely one of the worst, most rude lecturers I've ever had. He's a good lecturer up until you ask him a question, in which he feels like his intelligence is being insulted. He is passive-aggressive at best if you ask him questions, and he is super adamant on little stuff. For example, he will pretty much deny any regrade request you make. On one of the homeworks, we we were told to create a SQL query and filter on a specific value and many people (myself included) did not check for the value's NULLity (because the comparison >, <, etc. operators implicitly check it), but he was so adamant on not giving credit to people who didn't include the NULLity check. He's just really annoying in my opinion, but it's a super useful class. Midterm was decently difficult, we'll see how final goes

This class is arguably the most useful and important class that I have taken at UCLA, joint top along with CS 32. Way more than just a SQL class, Professor Rosario provides a holistic overview of the entire database system. He would often share with us his personal experiences and tips in industry, which I really appreciate since most other professors don't do that. While the first half of the class is mostly focused on SQL and Relational Algebra, the second half includes interesting topics such as Data Warehousing, Streaming Systems and NoSQL. Towards the final parts of the class, we dived even deeper into the hardware aspects, such as data storage, which felt slightly dry at times but definitely integral for those who aim to become data engineers.

Homework assignments were mostly well-crafted and fun to work on, especially Assignments 5 and 6 where we had to write queries in Spark SQL, MongoDB and Neo4j. The only downside of this class is Rosario's fast-paced lectures and tough exams. He goes at the speed of a Shinkansen during lecture, but fortunately he records them so I can re-watch to consolidate my learning. Exams are a time-crunch with never-ending questions, but each question itself is actually not too challenging as long as you are well-prepared.

I was searching for data science internships while taking CS 143, and it has been extremely helpful in tackling SQL interview questions, as well as expanding my knowledge in database systems. Now that I have secured an internship, looking back in hindsight, this class has played a pivotal role in my success. For anyone looking to enter the field of Data Science/Data Engineering/Software Engineering, I would highly recommend this class with Rosario.