Excel to MySQL: Analytic Techniques for Business

While the instructor does explain the subject well, there is a big gap between the material covered in the lectures and the material required for the assignments and quizzes. The first course in this certificate was mostly linear in progression (without too many gaps) but the second course (Excel) went off the rails.

I did watch the lectures but when I got to the quizzes and assignments, I found myself lost and not knowing how to work through the problems that were presented. Trying to work through it, I turned to the forums. The forums, however, were laregely managed by one TA-like figure that kept responding to new (and rececent) questions with 'please see previous explination' and 'I've already answered this elsewhere'. This TA has been "helping" with the course for years and then in order to find the correct post, you have to filter through years worth of posts to find one that actually explains the step by step process to follow. In some instances, you would have other students try and explain how to work through a problem (from a quiz) but their terminology is different than the instructor's and there would be a gap in the key phrases that you need to actually connect what is being requested by the quiz and how to look up a step by step process - resulting in you either already having to know the subject to look up information for the quiz, or you would have to guess at it.

Trying to take a quiz on the material that was not covered and not being able to find an explanation on the forums without filtering through "see response elsewhere" is not how I like to spend my money. I canceled my subscription/enrollment for this course.

Many problems with this specialization
There are many problematic issues with this course, and specialization in general.
1. The theoretical level is sometimes too high and too archane/complex: I don't know how students with no background training on some of the topics (e.g., modelling, statistics, regression analysis, ...) can pass this course within the alloted time frame. A basic statistical knowledge should either be required or included in the curriculum of this course (perhaps as a stand-alone course).
2. The 4th course, on SQL, suffers from serious technical issues: you are supposed use webpages that provide you access to the databases you need to learn and to complete your assignments, but these webpages are down and inaccessible many times during every single week of the course (this has been not only my own experience, but also that of many co-students who have fill tons of complaints about it). Neither the teaching staff, Duke University or Coursera seem to have done anything to address these issues.
I would certainly not recommend this specialization to anyone; instead, look for alternative options, there are many of them (e.g., on EdX and others)!!!