good

good

good

Good

good

good

Good

Good

good

good

Eas

gd

ok

3

.

V

The lectures and weekly coursework were fine -- although a bit too easy. The emphasis on certain aspects, such as formatting/commenting, and some comments on joins were on point. Sadie has a soothing voice and good pace, although the content somewhat drags at places. Not her fault as a presenter, the videos were just going too slow imo. There were a few typos in the lecture slides, one of which was quite confusing (I have reported them separately).

Unfortunately what really stood out in a negative way was the peer-graded assignment. This *really* needs to be rewritten. Specific problems:

Part1

=====

Questions 5 to 7 could be answered in two different ways: one, which is the "easier" one and the one that the marking guide forced us to accept, is to read off review_count from the Business table (and descend-order it). The first few results this way are

+-----------------+---------+

| city | reviews |

+-----------------+---------+

| Las Vegas | 82854 |

| Phoenix | 34503 |

| Toronto | 24113 |

| Scottsdale | 20614 |

| Charlotte | 12523 |

| Henderson | 10871 |

+-----------------+---------+

The problem with this is that the data set we're working on is a SUBSET of the full Yelp set. This means that the Business.review_count column (which was presumably added there in a redundant, denormalized way, in order to speed up queries) contains much higher counts than the ones that would be obtained by actually joining the Business and Review tables (on business id) and grouping by city. Here are the first few results of this approach, which imo is the correct one:

+-----------------+---------+

| city | reviews |

+-----------------+---------+

| Las Vegas | 193 |

| Phoenix | 65 |

| Toronto | 51 |

| Scottsdale | 37 |

| Henderson | 30 |

| Tempe | 28 |

+-----------------+---------+

I would be totally ok if the marking guide gave us the choice to accept both methods, but that wasn't the case.

Part 2

======

Q1 of Part2 was badly worded and unclear. It asks us to "pick a city AND a category" but then to group the businesses (by star rating) "in that city OR category". What exactly does that mean? Lump together all businesses from eg Phoenix (regardless of category) with the eg Restaurants businesses (regardless of city)? What's the rationale behind this? Or was it meant to read "in that city AND category" (meaning that we would only consider restaurants from Phoenix)?

Also, Q1.iii is both random and vague: why location? What do you mean by location (zip code? longitude/latitude?). This ties to the above ambiguity (X=AND vs X=OR in "in that city X category").

This is the worst specialization I have taken so far on Coursera, and I have taken several, either from universities or private companies.

The first course is fine for someone who already has SQL knowledge and just needs a refresher, but it is still a course with zero depth in the use of SQL in data science. It is just slides, better explanations of SQL can be found on YouTube.

The second course shows an interesting use of SQL, which is not normally covered. But the structure, assessments, assignments and final project are very open and ambiguous. The explanations are superfluous and you can tell that the course was made in a hurry, with no attention to details and with deficiencies in teaching.

Perhaps the third course is the best, as they present a useful technology and platform.

The final project is a total disappointment, as it is not focused on SQL and its use in Data Science activities, the videos are largely a recycling of those seen in previous courses, so that SQL, which is what the specialization is about, you do not learn something new or have the opportunity to apply it as it really applies in Data Science. Better SQL projects are found on YouTube, but these do not give a certificate endorsed by an educational institution such as the University of California, Davis. Sad that the readings in week four are links to other courses, they did not bother to create material or even reference it in a better way.

Zero material is shared.

After this experience I think I will not take any other course or specialization of this University, as well as not recommend it, I finished it just to receive the certificate, but I think it is not worth spending time on it.

Great as far as getting me to use more SQL and get better at writing queries. However, the peer reviewed assignment not only feels limited, it feels like people can get away with terrible work.

The limitations of the assignment are a small dataset, and limited SQL sandbox preventing us from using more complex queries using temporary tables (which are supported by SQLite). The output is also always limited to 25 row (this is for good reason, but it feels annoying to have to index which results I want if I want more than 25). I would also like to be able to pull the data out of SQL for analysis.

In terms of academic integrity, the grading felt like I was alternating between grading SQL code itself and the interpretation of the results. Since this course was mainly a SQL tutorial, I would have expected it to be more geared towards grading the SQL code. However, most of the assignment points went to interpretations and approach. Each question needs to have the point values changed to reflect the importance of SQL coding and reduce the value of interpretation.

Half of the submissions I was given to grade were incomplete. All the grades I recieved were full scores (not a brag) and I feel like this was due to people just selecting the full credit for each question without fully digesting what I had written. I didn't even have the full output for my final question and people still gave me full credit. That makes me very suspicious that people can complete this course if they submit something that really shouldn't pass, and brush past the peer grading by giving full scores without actually digesting the submission.

Overall rating: The course itself was really good for beginners. I really like SQL

Pro:

You get a lot of information and it has a clear structure.

There are nice examples and you can train enough.

The rate of speaking of the teacher was perfect for me.

A very good thing was that the questions of the exam fit perfectly well to the information we were taught in the classes.

Contra:

What i did not like is, that even though you get clear instructions how to write and structure your code, the teacher did not stick to the rules all the time or structured the code in a way, which was not mentioned before.

The reason why i only give 3 stars to this course is that the final assignment was the worst thing i ever experienced in a course. The instructions very totally unclear a lot of times and I had to search the discussion forum to find out what the questions are about. They could be interpreted in many different ways. Additionally, sometimes specific things were asked for like correlation, which is simply not possible if you take the question seriously. This would be a complicated formula, but the real intention of the question was to check it roughly by eye. But you can not tell what the intention is before you know the result and so it took me a lot of time to find out what the intention of several questions was. According to the discussion forum this problem is know for several years now. So enough time to fix it. Therefore i took two stars from the course.

Coming from someone who has zero experience using SQL, I can only describe this course as okay. On one hand I was able to build somewhat of a foundation seeing that I had no information prior to this course, alternatively the presentation of material especially as we approached week 3 was subpar. Week 3 and 4 had material that was much more involved and complicated compared to the prior weeks. The lectures were not at all sufficient enough to get a good understanding of the material. I found I had to find clarity using online tools, posting multiple (frequently unanswered) questions in the forum, and searching through pages and pages of forum posts in hopes that someone would have the same question I did. Painstakingly going through the lecture transcript on a specific topic was generally the last resort. To briefly speak more about the lecture delivery, I found it distractingly rehearsed. It's as if the material wasn't reviewed before reading it word for word to the students. There were so many misreads and phrases that made zero sense and these mistakes were carried through even to the most difficult concepts where a succinct, clear, informative delivery is desperately needed. I honestly felt like I was floundering in week 3 and especially week 4. The peer assignment questions were unclear and seemed to be asking questions on material we haven't covered or haven't covered in depth enough to answer some of the questions.

The content is good, but the presentation is not.

TL;DR: course is long for the amount of content; the content is good, but not how it is presented. I would have preferred more coding examples, syntax explanation, and practice rather than so much talk about little things that do not add to learning SQL.

First, the course could be condensed to at least half the time with the same amount of content. Videos are too long for the amount of content presented. She speaks clearly but gives a lot of intro and conclusions, repeating the same, and things not really valuable in terms of how to use SQL.

Second, the presentation is not good. The slides could be upgraded, and she needs to talk more about the code syntax. She gives the least importance to syntax and explaining the code; she only reads it. Given how many minutes/hours or videos the course have, it's really unbelievable so little of it is actually dedicated to coding; in the end, we are all here for that!

Third, I would have also prefere more coding practice.

And last but not least, I think some basics were missing. We didn't learn how to save a new table. We learned how to retrieve/join different ones...but not how to save them. I mean, sure, we can google it...but...again, the course is way too long not to cover that.

In general, course was not bad as for me, but there are some problems. On my opinion, main problem is luck of practice. Teacher tell about everything but all you see is explaining idea and purposes of using some statement, then boom and whole code on your screen, and you just seat and don't interact with SQL while listening the lecture. It was easier for me, since I've already knew some basics from another course, but I would definitely struggle if this was my first course in SQL. Also, in the beginning some task seemed to be given earlier then material needed for them. And the last problem is the last assignment. It seemed interesting for me at the beginning, but in the middle I got stuck with questions, cause they was made with hope on knowledge of student and, as I found out later, one of them doesn't have a certain answer. The most challenging was the last task in the assignment but problem was again in understanding what is needed from you, not in difficulty of writing some SQL code. It would be better, if links on useful sources were given before last assignment, so people at least had idea what to do and get some additional knowledge at the same time. At the same time, course have structure and some practical tests, so that's why I give it 3 stars.

Tl:dr - Peer review delays completion. If crunched for time, avoid. Directions for final could be better. Decent coursework and flow. 4/5 is structure were to be changed.

- Peer Review takes too long! If you are taking this course on a deadline or trying to bolster your resume while applying for jobs, avoid this course. If you have the time and leisure to take it, do so, the material is informative without too much fluff. - The SQL SandBox for the final exam is very poorly explained and overall seemingly pointless to the completion of the coursework. A good standalone resource, but confusing without proper guidance.

- I tried taking this course on the 7-day free trial, completing the 4-week course within a 3 day period (very doable), but am stuck at 98% complete waiting for a peer review (grading) of my final assignment. There is no incentivization for peer reviewing beyond being required to peer review 4 assignments, whereas there should be a system such as; the more you review in a timely manner, the more likely yours is to be reviewed timely. Worried I will have to pay the premium price for Coursera just to get the completion in this course. Absolutely ridiculous, and a major oversight in the design structure of this course.

The course is a good starting point for learning SQL but it is limited to SELECT statements only. There are some errors here and there that you can generally overlook but may confuse you if you are already struggling with the concepts. The two big negatives in my opinion were the way concepts are presented and the final assignment. The concept are presented by a lady who just speaks and part of the screen shows the SQL she is referencing without breaking down the code into parts so that the student can understand it. It would be much more effective if the code was "created" on the screen. The biggest issue with understanding the code is that the instructor never shares a view of the database that the SQL code are working on (even though there is a lot of emphasis given in the lecture to "first spend time getting familiar with your dataset". It would have helped if the student was given a chance to familiarize himself with the data used in the examples. As for the final assignment, the instructions were vague and it took me a lot more time to figure out what was being asked than to actually do the coding to answer the question.